2013 |
Crivillers, Nuria ; Osella, Silvio ; Van Dyck, Colin ; Lazzerini, Giovanni M; Cornil, David ; Liscio, Andrea ; Di Stasio, Francesco ; Mian, Shabbir ; Fenwick, Oliver ; Reinders, Federica ; Neuburger, Markus ; Treossi, Emanuele ; Mayor, Marcel ; Palermo, Vincenzo ; Cacialli, Franco ; Cornil, Jerome ; Samori, Paolo Large Work Function Shift of Gold Induced by a Novel Perfluorinated Azobenzene-Based Self-Assembled Monolayer Journal Article In: ADVANCED MATERIALS, 25 (3, SI), pp. 432–436, 2013, ISSN: 0935-9648. @article{crivillers_large_2013, title = {Large Work Function Shift of Gold Induced by a Novel Perfluorinated Azobenzene-Based Self-Assembled Monolayer}, author = {Crivillers, Nuria and Osella, Silvio and Van Dyck, Colin and Lazzerini, Giovanni M. and Cornil, David and Liscio, Andrea and Di Stasio, Francesco and Mian, Shabbir and Fenwick, Oliver and Reinders, Federica and Neuburger, Markus and Treossi, Emanuele and Mayor, Marcel and Palermo, Vincenzo and Cacialli, Franco and Cornil, Jerome and Samori, Paolo}, doi = {10.1002/adma.201201737}, issn = {0935-9648}, year = {2013}, date = {2013-01-01}, journal = {ADVANCED MATERIALS}, volume = {25}, number = {3, SI}, pages = {432--436}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Musumeci, Chiara ; Hutchison, James A; Samori, Paolo Controlling the morphology of conductive PEDOT by in situ electropolymerization: from thin films to nanowires with variable electrical properties Journal Article In: NANOSCALE, 5 (17), pp. 7756–7761, 2013, ISSN: 2040-3364. @article{musumeci_controlling_2013, title = {Controlling the morphology of conductive PEDOT by in situ electropolymerization: from thin films to nanowires with variable electrical properties}, author = {Musumeci, Chiara and Hutchison, James A. and Samori, Paolo}, doi = {10.1039/c3nr03093h}, issn = {2040-3364}, year = {2013}, date = {2013-01-01}, journal = {NANOSCALE}, volume = {5}, number = {17}, pages = {7756--7761}, abstract = {The controlled electrochemical synthesis of poly(3,4-ethylenedioxythiophene) (PEDOT) as a model conjugated polymer is described here. We show that the morphology of electrochemically synthesized PEDOT can be finely tuned directly in a device, by carefully guiding the nucleation and growth processes as well as electromigration phenomena, resulting in structures with variable electrical properties.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The controlled electrochemical synthesis of poly(3,4-ethylenedioxythiophene) (PEDOT) as a model conjugated polymer is described here. We show that the morphology of electrochemically synthesized PEDOT can be finely tuned directly in a device, by carefully guiding the nucleation and growth processes as well as electromigration phenomena, resulting in structures with variable electrical properties. |
Ciesielski, Artur ; Haar, Sebastien ; Paragi, Gabor ; Kupihar, Zoltan ; Kele, Zoltan ; Masiero, Stefano ; Guerra, Celia Fonseca ; Bickelhaupt, Matthias F; Spada, Gian Piero ; Kovacs, Lajos ; Samori, Paolo Supramolecular Ħ-bonded porous networks at surfaces: exploiting primary and secondary interactions in a bi-component melamine-xanthine system Journal Article In: PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 15 (30), pp. 12442–12446, 2013, ISSN: 1463-9076. @article{ciesielski_supramolecular_2013, title = {Supramolecular Ħ-bonded porous networks at surfaces: exploiting primary and secondary interactions in a bi-component melamine-xanthine system}, author = {Ciesielski, Artur and Haar, Sebastien and Paragi, Gabor and Kupihar, Zoltan and Kele, Zoltan and Masiero, Stefano and Guerra, Celia Fonseca and Bickelhaupt, F. Matthias and Spada, Gian Piero and Kovacs, Lajos and Samori, Paolo}, doi = {10.1039/c3cp50891a}, issn = {1463-9076}, year = {2013}, date = {2013-01-01}, journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS}, volume = {15}, number = {30}, pages = {12442--12446}, abstract = {The control over the formation of a bi-component porous network was attained by the self-assembly at a solid-liquid interface by exploiting both primary and secondary non-covalent interactions between melamine and N-3-alkylated xanthine modules.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The control over the formation of a bi-component porous network was attained by the self-assembly at a solid-liquid interface by exploiting both primary and secondary non-covalent interactions between melamine and N-3-alkylated xanthine modules. |
Schlierf, Andrea ; Yang, Huafeng ; Gebremedhn, Elias ; Treossi, Emanuele ; Ortolani, Luca ; Chen, Liping ; Minoia, Andrea ; Morandi, Vittorio ; Samori, Paolo ; Casiraghi, Cinzia ; Beljonne, David ; Palermo, Vincenzo Nanoscale insight into the exfoliation mechanism of graphene with organic dyes: effect of charge, dipole and molecular structure Journal Article In: NANOSCALE, 5 (10), pp. 4205–4216, 2013, ISSN: 2040-3364. @article{schlierf_nanoscale_2013, title = {Nanoscale insight into the exfoliation mechanism of graphene with organic dyes: effect of charge, dipole and molecular structure}, author = {Schlierf, Andrea and Yang, Huafeng and Gebremedhn, Elias and Treossi, Emanuele and Ortolani, Luca and Chen, Liping and Minoia, Andrea and Morandi, Vittorio and Samori, Paolo and Casiraghi, Cinzia and Beljonne, David and Palermo, Vincenzo}, doi = {10.1039/c3nr00258f}, issn = {2040-3364}, year = {2013}, date = {2013-01-01}, journal = {NANOSCALE}, volume = {5}, number = {10}, pages = {4205--4216}, abstract = {We study the mechanism of surface adsorption of organic dyes on graphene, and successive exfoliation in water of these dye-functionalized graphene sheets. A systematic, comparative study is performed on pyrenes functionalized with an increasing number of sulfonic groups. By combining experimental and modeling investigations, we find an unambiguous correlation between the graphene-dye interaction energy, the molecular structure and the amount of graphene flakes solubilized. The results obtained indicate that the molecular dipole is not important per se, but because it facilitates adsorption on graphene by a “sliding” mechanism of the molecule into the solvent layer, facilitating the lateral displacement of the water molecules collocated between the aromatic cores of the dye and graphene. While a large dipole and molecular asymmetry promote the adsorption of the molecule on graphene, the stability and pH response of the suspensions obtained depend on colloidal stabilization, with no significant influence of molecular charging and dipole.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We study the mechanism of surface adsorption of organic dyes on graphene, and successive exfoliation in water of these dye-functionalized graphene sheets. A systematic, comparative study is performed on pyrenes functionalized with an increasing number of sulfonic groups. By combining experimental and modeling investigations, we find an unambiguous correlation between the graphene-dye interaction energy, the molecular structure and the amount of graphene flakes solubilized. The results obtained indicate that the molecular dipole is not important per se, but because it facilitates adsorption on graphene by a “sliding” mechanism of the molecule into the solvent layer, facilitating the lateral displacement of the water molecules collocated between the aromatic cores of the dye and graphene. While a large dipole and molecular asymmetry promote the adsorption of the molecule on graphene, the stability and pH response of the suspensions obtained depend on colloidal stabilization, with no significant influence of molecular charging and dipole. |
De Luca, Giovanna ; Liscio, Andrea ; Battagliarin, Glauco ; Chen, Long ; Scolaro, Luigi Monsu ; Muellen, Klaus ; Samori, Paolo ; Palermo, Vincenzo Orthogonal self-assembly and selective solvent vapour annealing: simplified processing of a photovoltaic blend Journal Article In: CHEMICAL COMMUNICATIONS, 49 (39), pp. 4322–4324, 2013, ISSN: 1359-7345. @article{de_luca_orthogonal_2013, title = {Orthogonal self-assembly and selective solvent vapour annealing: simplified processing of a photovoltaic blend}, author = {De Luca, Giovanna and Liscio, Andrea and Battagliarin, Glauco and Chen, Long and Scolaro, Luigi Monsu and Muellen, Klaus and Samori, Paolo and Palermo, Vincenzo}, doi = {10.1039/c2cc37909k}, issn = {1359-7345}, year = {2013}, date = {2013-01-01}, journal = {CHEMICAL COMMUNICATIONS}, volume = {49}, number = {39}, pages = {4322--4324}, abstract = {Selective solvent vapour annealing is used on a photovoltaic blend to enhance the interaction between the electron acceptor and the electron donor, simplifying thin films post-processing for photovoltaic applications. A remarkable improvement in the interfacial charge transfer in the bulk hetero-junction is attained, as measured by Kelvin Probe Force Microscopy.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Selective solvent vapour annealing is used on a photovoltaic blend to enhance the interaction between the electron acceptor and the electron donor, simplifying thin films post-processing for photovoltaic applications. A remarkable improvement in the interfacial charge transfer in the bulk hetero-junction is attained, as measured by Kelvin Probe Force Microscopy. |
Ovchinnikov, Victor ; Cecchini, Marco ; Karplus, Martin A Simplified Confinement Method for Calculating Absolute Free Energies and Free Energy and Entropy Differences Journal Article In: JOURNAL OF PHYSICAL CHEMISTRY B, 117 (3), pp. 750–762, 2013, ISSN: 1520-6106. @article{ovchinnikov_simplified_2013, title = {A Simplified Confinement Method for Calculating Absolute Free Energies and Free Energy and Entropy Differences}, author = {Ovchinnikov, Victor and Cecchini, Marco and Karplus, Martin}, doi = {10.1021/jp3080578}, issn = {1520-6106}, year = {2013}, date = {2013-01-01}, journal = {JOURNAL OF PHYSICAL CHEMISTRY B}, volume = {117}, number = {3}, pages = {750--762}, abstract = {A simple and robust formulation of the path-independent confinement method for the calculation of free energies is presented. The simplified confinement method (SCM) does not require matrix diagonalization or switching off the molecular force field, and has a simple convergence criterion. The method can be readily implemented in molecular dynamics programs with minimal or no code modifications. Because the confinement method is a special case of thermodynamic integration, it is trivially parallel over the integration variable. The accuracy of the method is demonstrated using a model diatomic molecule, for which exact results can be computed analytically. The method is then applied to the alanine dipeptide in vacuum, and to the alpha-helix textbackslashtextbackslashtextless-textbackslashtextbackslashtextgreater beta-sheet transition in a 16-residue peptide modeled in implicit solvent. The SCM requires less effort for the calculation of free energy differences than previous formulations because it does not require computing normal modes. The SCM has a diminished advantage for determining absolute free energy values, because it requires decreasing the MD integration step to obtain accurate results. An approximate confinement procedure is introduced, which can be used to estimate directly the configurational entropy difference between two macrostates, without the need for additional computation of the difference in the free energy or enthalpy. The approximation has convergence properties similar to those of the standard confinement method for the calculation of free energies. The use of the approximation requires about 5 times less wall-clock simulation time than that needed to compute enthalpy differences to similar precision from an MD trajectory. For the biomolecular systems considered in this study, the errors in the entropy approximation are under 10%. Practical applications of the methods to proteins are currently limited to implicit solvent simulations.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A simple and robust formulation of the path-independent confinement method for the calculation of free energies is presented. The simplified confinement method (SCM) does not require matrix diagonalization or switching off the molecular force field, and has a simple convergence criterion. The method can be readily implemented in molecular dynamics programs with minimal or no code modifications. Because the confinement method is a special case of thermodynamic integration, it is trivially parallel over the integration variable. The accuracy of the method is demonstrated using a model diatomic molecule, for which exact results can be computed analytically. The method is then applied to the alanine dipeptide in vacuum, and to the alpha-helix textbackslashtextbackslashtextless-textbackslashtextbackslashtextgreater beta-sheet transition in a 16-residue peptide modeled in implicit solvent. The SCM requires less effort for the calculation of free energy differences than previous formulations because it does not require computing normal modes. The SCM has a diminished advantage for determining absolute free energy values, because it requires decreasing the MD integration step to obtain accurate results. An approximate confinement procedure is introduced, which can be used to estimate directly the configurational entropy difference between two macrostates, without the need for additional computation of the difference in the free energy or enthalpy. The approximation has convergence properties similar to those of the standard confinement method for the calculation of free energies. The use of the approximation requires about 5 times less wall-clock simulation time than that needed to compute enthalpy differences to similar precision from an MD trajectory. For the biomolecular systems considered in this study, the errors in the entropy approximation are under 10%. Practical applications of the methods to proteins are currently limited to implicit solvent simulations. |
Stefankiewicz, Artur R; Harrowfield, Jack ; Madalan, Augustin M; Lehn, Jean-Marie Tuning the planarity of [2 x 2] grids Journal Article In: CRYSTENGCOMM, 15 (44), pp. 9128–9134, 2013, ISSN: 1466-8033. @article{stefankiewicz_tuning_2013, title = {Tuning the planarity of [2 x 2] grids}, author = {Stefankiewicz, Artur R. and Harrowfield, Jack and Madalan, Augustin M. and Lehn, Jean-Marie}, doi = {10.1039/c3ce41510d}, issn = {1466-8033}, year = {2013}, date = {2013-01-01}, journal = {CRYSTENGCOMM}, volume = {15}, number = {44}, pages = {9128--9134}, abstract = {New [2 x 2] metallogrids derived from a ditopic ligand with terminal salicylaldimine binding sites giving six-membered chelate rings have been structurally characterised in order to determine the effect of ring size variation on the planarity of the core M-4 unit. Both the Zn-4 unit of the grid formed from the neutral ligand and the Fe-4 unit of the grid formed from the doubly deprotonated ligand are very close to planar, despite considerable differences in the coordination spheres of the two metal ions and the difference in their oxidation states (Zn(II), Fe(III)).}, keywords = {}, pubstate = {published}, tppubtype = {article} } New [2 x 2] metallogrids derived from a ditopic ligand with terminal salicylaldimine binding sites giving six-membered chelate rings have been structurally characterised in order to determine the effect of ring size variation on the planarity of the core M-4 unit. Both the Zn-4 unit of the grid formed from the neutral ligand and the Fe-4 unit of the grid formed from the doubly deprotonated ligand are very close to planar, despite considerable differences in the coordination spheres of the two metal ions and the difference in their oxidation states (Zn(II), Fe(III)). |
Stadler, Adrian-Mihail ; Burg, Christophe ; Ramirez, Juan ; Lehn, Jean-Marie Grid-double-helicate interconversion Journal Article In: CHEMICAL COMMUNICATIONS, 49 (51), pp. 5733–5735, 2013, ISSN: 1359-7345. @article{stadler_grid-double-helicate_2013, title = {Grid-double-helicate interconversion}, author = {Stadler, Adrian-Mihail and Burg, Christophe and Ramirez, Juan and Lehn, Jean-Marie}, doi = {10.1039/c3cc38580a}, issn = {1359-7345}, year = {2013}, date = {2013-01-01}, journal = {CHEMICAL COMMUNICATIONS}, volume = {49}, number = {51}, pages = {5733--5735}, abstract = {An interconversion between a binuclear Cu-I double helicate and a tetranuclear Cu-II grid is reported. The passage from the Cu-I double helicate to the Cu-II grid occurs through oxidation of Cu-I into Cu-II or through displacement of CuI by Cu-II. The conversion of the CuII grid into the Cu-I double helicate occurs through treatment of the grid with triflic acid, reduction of Cu-II with ascorbic acid, and neutralization with triethylamine. During the studies, in order to ascertain the structure of Cu-I complexes, a heteroleptic binuclear Cu-I double helicate was generated.}, keywords = {}, pubstate = {published}, tppubtype = {article} } An interconversion between a binuclear Cu-I double helicate and a tetranuclear Cu-II grid is reported. The passage from the Cu-I double helicate to the Cu-II grid occurs through oxidation of Cu-I into Cu-II or through displacement of CuI by Cu-II. The conversion of the CuII grid into the Cu-I double helicate occurs through treatment of the grid with triflic acid, reduction of Cu-II with ascorbic acid, and neutralization with triethylamine. During the studies, in order to ascertain the structure of Cu-I complexes, a heteroleptic binuclear Cu-I double helicate was generated. |
Roy, Nabarun ; Buhler, Eric ; Lehn, Jean-Marie Generation of supramolecular microcapsules by oxidative covalent polymerization of a ditopic supramolecular building block Journal Article In: POLYMER CHEMISTRY, 4 (10), pp. 2949–2957, 2013, ISSN: 1759-9954. @article{roy_generation_2013, title = {Generation of supramolecular microcapsules by oxidative covalent polymerization of a ditopic supramolecular building block}, author = {Roy, Nabarun and Buhler, Eric and Lehn, Jean-Marie}, doi = {10.1039/c3py00308f}, issn = {1759-9954}, year = {2013}, date = {2013-01-01}, journal = {POLYMER CHEMISTRY}, volume = {4}, number = {10}, pages = {2949--2957}, abstract = {We describe a novel approach to the generation of a supramolecular polymer and its assembly into microcapsules by the aerial oxidation of a supramolecular building block. It involves the initial build-up of a ditopic supramolecular component by hydrogen bonding association of two complementary subunits, followed by its covalent polymerization through oxidative formation of C-C linkages. The supramolecular component itself was selectively formed from a dynamic covalent library of hydrazone isomers by target specific amplification of a single library constituent. The polymer obtained condenses into supramolecular aggregates of micrometric size and capsular-type morphology, presenting multilayered walls, which have been characterized by STEM, SEM and AFM imaging methods. The present design methodology implements the covalent polycondensation of non-covalent monomers towards the formation of supramolecular polymers, in a sequence opposite to the usual non-covalent polyassociation of covalent complementary monomers. It can be envisaged as a proactive step towards forming adaptive smart materials through manipulation of the sequence of supramolecular/noncovalent and molecular/covalent steps for the generation of supramolecular polymers by suitable selection of receptor and substrate moieties.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We describe a novel approach to the generation of a supramolecular polymer and its assembly into microcapsules by the aerial oxidation of a supramolecular building block. It involves the initial build-up of a ditopic supramolecular component by hydrogen bonding association of two complementary subunits, followed by its covalent polymerization through oxidative formation of C-C linkages. The supramolecular component itself was selectively formed from a dynamic covalent library of hydrazone isomers by target specific amplification of a single library constituent. The polymer obtained condenses into supramolecular aggregates of micrometric size and capsular-type morphology, presenting multilayered walls, which have been characterized by STEM, SEM and AFM imaging methods. The present design methodology implements the covalent polycondensation of non-covalent monomers towards the formation of supramolecular polymers, in a sequence opposite to the usual non-covalent polyassociation of covalent complementary monomers. It can be envisaged as a proactive step towards forming adaptive smart materials through manipulation of the sequence of supramolecular/noncovalent and molecular/covalent steps for the generation of supramolecular polymers by suitable selection of receptor and substrate moieties. |
Vantomme, Ghislaine ; Lehn, Jean-Marie Photo- and Thermoresponsive Supramolecular Assemblies: Reversible Photorelease of K plus Ions and Constitutional Dynamics Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 52 (14), pp. 3940–3943, 2013, ISSN: 1433-7851. @article{vantomme_photo-_2013, title = {Photo- and Thermoresponsive Supramolecular Assemblies: Reversible Photorelease of K plus Ions and Constitutional Dynamics}, author = {Vantomme, Ghislaine and Lehn, Jean-Marie}, doi = {10.1002/anie.201210334}, issn = {1433-7851}, year = {2013}, date = {2013-01-01}, journal = {ANGEWANDTE CHEMIE-INTERNATIONAL EDITION}, volume = {52}, number = {14}, pages = {3940--3943}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Hermans, Thomas M; Pilans, Didzis ; Huda, Sabil ; Fuller, Patrick ; Kandere-Grzybowska, Kristiana ; Grzybowski, Bartosz A Motility efficiency and spatiotemporal synchronization in non-metastatic vs. metastatic breast cancer cells Journal Article In: INTEGRATIVE BIOLOGY, 5 (12), pp. 1464–1473, 2013, ISSN: 1757-9694. @article{hermans_motility_2013, title = {Motility efficiency and spatiotemporal synchronization in non-metastatic vs. metastatic breast cancer cells}, author = {Hermans, Thomas M. and Pilans, Didzis and Huda, Sabil and Fuller, Patrick and Kandere-Grzybowska, Kristiana and Grzybowski, Bartosz A.}, doi = {10.1039/c3ib40144h}, issn = {1757-9694}, year = {2013}, date = {2013-01-01}, journal = {INTEGRATIVE BIOLOGY}, volume = {5}, number = {12}, pages = {1464--1473}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Safavi-Naini, A; Soeyler, S G; Pupillo, G; Sadeghpour, H R; Capogrosso-Sansone, B Quantum phases of dipolar bosons in bilayer geometry Journal Article In: NEW JOURNAL OF PHYSICS, 15 , 2013, ISSN: 1367-2630. @article{safavi-naini_quantum_2013, title = {Quantum phases of dipolar bosons in bilayer geometry}, author = {Safavi-Naini, A. and Soeyler, S. G. and Pupillo, G. and Sadeghpour, H. R. and Capogrosso-Sansone, B.}, doi = {10.1088/1367-2630/15/1/013036}, issn = {1367-2630}, year = {2013}, date = {2013-01-01}, journal = {NEW JOURNAL OF PHYSICS}, volume = {15}, abstract = {We investigate the quantum phases of hard-core dipolar bosons confined to a square lattice in a bilayer geometry. Using exact theoretical techniques, we discuss the many-body effects resulting from the pairing of particles across layers at finite density, including a novel pair supersolid, superfluid and solid phases. These results are of direct relevance to experiments with polar molecules and atoms with large magnetic dipole moments trapped in optical lattices.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We investigate the quantum phases of hard-core dipolar bosons confined to a square lattice in a bilayer geometry. Using exact theoretical techniques, we discuss the many-body effects resulting from the pairing of particles across layers at finite density, including a novel pair supersolid, superfluid and solid phases. These results are of direct relevance to experiments with polar molecules and atoms with large magnetic dipole moments trapped in optical lattices. |
Niess, Frederic ; Sauvage, Jean-Pierre Synthesis of a metal-free coordinating ring via formation of a cleavable [2]catenane Journal Article In: CHEMICAL COMMUNICATIONS, 49 (92), pp. 10790–10792, 2013, ISSN: 1359-7345. @article{niess_synthesis_2013, title = {Synthesis of a metal-free coordinating ring via formation of a cleavable [2]catenane}, author = {Niess, Frederic and Sauvage, Jean-Pierre}, doi = {10.1039/c3cc46452k}, issn = {1359-7345}, year = {2013}, date = {2013-01-01}, journal = {CHEMICAL COMMUNICATIONS}, volume = {49}, number = {92}, pages = {10790--10792}, abstract = {We describe an efficient methodology which allows for the preparation of a macrocycle incorporating a free coordination site. It is based on a transition metal-templated strategy and RCM to provide access to a Cu(I)-complexed [2] catenane consisting of the desired cyclised compound and a cleavable ring. Release of the cleavable ring leads to the formation of the target macrocycle in quantitative yield.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We describe an efficient methodology which allows for the preparation of a macrocycle incorporating a free coordination site. It is based on a transition metal-templated strategy and RCM to provide access to a Cu(I)-complexed [2] catenane consisting of the desired cyclised compound and a cleavable ring. Release of the cleavable ring leads to the formation of the target macrocycle in quantitative yield. |
Mohankumar, Meera ; Holler, Michel ; Schmitt, Michel ; Sauvage, Jean-Pierre ; Nierengarten, Jean-Franois Dynamic topomerization of Cu(I)-complexed pseudorotaxanes Journal Article In: CHEMICAL COMMUNICATIONS, 49 (13), pp. 1261–1263, 2013, ISSN: 1359-7345. @article{mohankumar_dynamic_2013, title = {Dynamic topomerization of Cu(I)-complexed pseudorotaxanes}, author = {Mohankumar, Meera and Holler, Michel and Schmitt, Michel and Sauvage, Jean-Pierre and Nierengarten, Jean-Franois}, doi = {10.1039/c2cc37724a}, issn = {1359-7345}, year = {2013}, date = {2013-01-01}, journal = {CHEMICAL COMMUNICATIONS}, volume = {49}, number = {13}, pages = {1261--1263}, abstract = {Dynamic molecular motions resulting from the folding of a flexible macrocyclic component in a Cu(I)-complexed pseudorotaxane have been evidenced by variable temperature NMR experiments. The proposed conformational changes are also supported by the X-ray crystal structures of the compounds and computational studies.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Dynamic molecular motions resulting from the folding of a flexible macrocyclic component in a Cu(I)-complexed pseudorotaxane have been evidenced by variable temperature NMR experiments. The proposed conformational changes are also supported by the X-ray crystal structures of the compounds and computational studies. |
Chambron, Jean-Claude ; Sauvage, Jean-Pierre Topologically complex molecules obtained by transition metal templation: it is the presentation that determines the synthesis strategy Journal Article In: NEW JOURNAL OF CHEMISTRY, 37 (1), pp. 49–57, 2013, ISSN: 1144-0546. @article{chambron_topologically_2013, title = {Topologically complex molecules obtained by transition metal templation: it is the presentation that determines the synthesis strategy}, author = {Chambron, Jean-Claude and Sauvage, Jean-Pierre}, doi = {10.1039/c2nj40555e}, issn = {1144-0546}, year = {2013}, date = {2013-01-01}, journal = {NEW JOURNAL OF CHEMISTRY}, volume = {37}, number = {1}, pages = {49--57}, abstract = {Topological constructions made from closed curves range from simple links to intricate knots and started to capture the chemists' attention in the early sixties. These mathematical objects result from particular embeddings of a single or a set of closed curves in the three-dimensional space that show an infinite variety of presentations. Simple catenanes, higher order interlocked macrocycles, and molecular knots can be synthesized via the metal template approach, just as simple macrocycles. However, this requires that rigid presentations with appropriate geometrical characteristics be identified prior to molecular design, and those selected for the metal-templated synthesis of some of these fascinating molecules are reviewed here.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Topological constructions made from closed curves range from simple links to intricate knots and started to capture the chemists' attention in the early sixties. These mathematical objects result from particular embeddings of a single or a set of closed curves in the three-dimensional space that show an infinite variety of presentations. Simple catenanes, higher order interlocked macrocycles, and molecular knots can be synthesized via the metal template approach, just as simple macrocycles. However, this requires that rigid presentations with appropriate geometrical characteristics be identified prior to molecular design, and those selected for the metal-templated synthesis of some of these fascinating molecules are reviewed here. |
Weber, Dennis ; Sharma, Richa ; Botnaras, Silviu ; Pham, Duy Vu ; Steiger, Juergen ; De Cola, Luisa Base-etch removal of a ligand shell in thin films of ZnO nanoparticles for electronic applications Journal Article In: JOURNAL OF MATERIALS CHEMISTRY C, 1 (42), pp. 7111–7116, 2013, ISSN: 2050-7526. @article{weber_base-etch_2013, title = {Base-etch removal of a ligand shell in thin films of ZnO nanoparticles for electronic applications}, author = {Weber, Dennis and Sharma, Richa and Botnaras, Silviu and Pham, Duy Vu and Steiger, Juergen and De Cola, Luisa}, doi = {10.1039/c3tc31059k}, issn = {2050-7526}, year = {2013}, date = {2013-01-01}, journal = {JOURNAL OF MATERIALS CHEMISTRY C}, volume = {1}, number = {42}, pages = {7111--7116}, abstract = {Functionalized nanoparticles offer many advantages regarding homogenous film formation. However, to utilize the semiconductive properties of metal oxides the insulating species on the particle's surface need to be removed. A widely employed route is the thermal decomposition of the ligands. If one wishes to lower the process temperature it is necessary to find alternative procedures. The organic nature of the ligand shell of octylamine-functionalized ZnO nanoparticles is a contrast to the properties of the inorganic metal oxide. This discrepancy is used to aid the ligand removal by potassium hydroxide etching. Wet etching processes are widespread in the semiconductor industry. We report on the beneficial effect of a mild base treatment on the electrical properties of ZnO-based thin-film transistors. The annealing temperatures can be drastically reduced; a field effect mobility value of 0.1 cm(2) V-1 s(-1) was obtained at a maximum process temperature of 350 degrees C.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Functionalized nanoparticles offer many advantages regarding homogenous film formation. However, to utilize the semiconductive properties of metal oxides the insulating species on the particle's surface need to be removed. A widely employed route is the thermal decomposition of the ligands. If one wishes to lower the process temperature it is necessary to find alternative procedures. The organic nature of the ligand shell of octylamine-functionalized ZnO nanoparticles is a contrast to the properties of the inorganic metal oxide. This discrepancy is used to aid the ligand removal by potassium hydroxide etching. Wet etching processes are widespread in the semiconductor industry. We report on the beneficial effect of a mild base treatment on the electrical properties of ZnO-based thin-film transistors. The annealing temperatures can be drastically reduced; a field effect mobility value of 0.1 cm(2) V-1 s(-1) was obtained at a maximum process temperature of 350 degrees C. |
Weber, Dennis ; Botnaras, Silviu ; Pham, Duy Vu ; Steiger, Juergen ; De Cola, Luisa Functionalized ZnO nanoparticles for thin-film transistors: support of ligand removal by non-thermal methods Journal Article In: JOURNAL OF MATERIALS CHEMISTRY C, 1 (18), pp. 3098–3103, 2013, ISSN: 2050-7526. @article{weber_functionalized_2013, title = {Functionalized ZnO nanoparticles for thin-film transistors: support of ligand removal by non-thermal methods}, author = {Weber, Dennis and Botnaras, Silviu and Pham, Duy Vu and Steiger, Juergen and De Cola, Luisa}, doi = {10.1039/c3tc00576c}, issn = {2050-7526}, year = {2013}, date = {2013-01-01}, journal = {JOURNAL OF MATERIALS CHEMISTRY C}, volume = {1}, number = {18}, pages = {3098--3103}, abstract = {A new approach is presented which allows substantial reduction of the process temperature of zinc oxide nanoparticles to generate semiconducting thin films. Functionalization is used to allow facile dispersion and to prevent agglomeration of the particles. Since charge transport is impeded by an insulating shell of octylamine the functionalization needs to be removed. Particles are deposited by spin-coating and the resulting film is exposed to different treatments. It is shown that plain annealing processes require high temperatures to fully remove the capping agents. The method presented in this work is a combination of UV irradiation of the wet films before annealing to cleave the octylamine and a vacuum process to aid the removal of organic residues. The effectiveness of the method is proven by electrical characterization.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A new approach is presented which allows substantial reduction of the process temperature of zinc oxide nanoparticles to generate semiconducting thin films. Functionalization is used to allow facile dispersion and to prevent agglomeration of the particles. Since charge transport is impeded by an insulating shell of octylamine the functionalization needs to be removed. Particles are deposited by spin-coating and the resulting film is exposed to different treatments. It is shown that plain annealing processes require high temperatures to fully remove the capping agents. The method presented in this work is a combination of UV irradiation of the wet films before annealing to cleave the octylamine and a vacuum process to aid the removal of organic residues. The effectiveness of the method is proven by electrical characterization. |
Azzouz, Nahid ; Kamena, Faustin ; Laurino, Paola ; Kikkeri, Raghavendra ; Mercier, Corinne ; Cesbron-Delauw, Marie-France ; Dubremetz, Jean-Francois ; De Cola, Luisa ; Seeberger, Peter H Toxoplasma gondii secretory proteins bind to sulfated heparin structures Journal Article In: GLYCOBIOLOGY, 23 (1), pp. 106–120, 2013, ISSN: 0959-6658. @article{azzouz_toxoplasma_2013, title = {Toxoplasma gondii secretory proteins bind to sulfated heparin structures}, author = {Azzouz, Nahid and Kamena, Faustin and Laurino, Paola and Kikkeri, Raghavendra and Mercier, Corinne and Cesbron-Delauw, Marie-France and Dubremetz, Jean-Francois and De Cola, Luisa and Seeberger, Peter H.}, doi = {10.1093/glycob/cws134}, issn = {0959-6658}, year = {2013}, date = {2013-01-01}, journal = {GLYCOBIOLOGY}, volume = {23}, number = {1}, pages = {106--120}, abstract = {Toxoplasma gondii is the causative agent of toxoplasmosis, one of the most widespread infections in humans and animals, and is a major opportunistic pathogen in immunocompromised patients. Toxoplasma gondii is unique as it can invade virtually any nucleated cell, although the mechanisms are not completely understood. Parasite attachment to the host cell is a prerequisite for reorientation and penetration and likely requires the recognition of molecules at the host cell surface. It has been reported that the affinity of tachyzoites, the invasive form of T. gondii, for host cells can be inhibited by a variety of soluble-sulfated glycosaminoglycans (GAGs), such as heparan sulfate. Using heparin-functionalized zeolites in the absence of host cells, we visualized heparin-binding sites on the surface of tachyzoites by confocal and atomic force microscopy. Furthermore, we report that protein components of the parasite rhoptry, dense granule and surface bind GAGs. In particular, the proteins ROP2 and ROP4 from the rhoptry, GRA2 from the dense granules and the surface protein SAG1 were found to bind heparin. The binding specificities and affinities of individual parasite proteins for natural heparin and heparin oligosaccharides were determined by a combination of heparin oligosaccharide microarrays and surface plasmon resonance. Our results suggest that interactions between sulfated GAGs and parasite surface antigens contribute to T. gondii attachment to host cell surfaces as well as initiating the invasion process, while rhoptries and dense granule organelles may play an important role during the establishment of the infection and during the life of the parasite inside the parasitophorous vacuole.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Toxoplasma gondii is the causative agent of toxoplasmosis, one of the most widespread infections in humans and animals, and is a major opportunistic pathogen in immunocompromised patients. Toxoplasma gondii is unique as it can invade virtually any nucleated cell, although the mechanisms are not completely understood. Parasite attachment to the host cell is a prerequisite for reorientation and penetration and likely requires the recognition of molecules at the host cell surface. It has been reported that the affinity of tachyzoites, the invasive form of T. gondii, for host cells can be inhibited by a variety of soluble-sulfated glycosaminoglycans (GAGs), such as heparan sulfate. Using heparin-functionalized zeolites in the absence of host cells, we visualized heparin-binding sites on the surface of tachyzoites by confocal and atomic force microscopy. Furthermore, we report that protein components of the parasite rhoptry, dense granule and surface bind GAGs. In particular, the proteins ROP2 and ROP4 from the rhoptry, GRA2 from the dense granules and the surface protein SAG1 were found to bind heparin. The binding specificities and affinities of individual parasite proteins for natural heparin and heparin oligosaccharides were determined by a combination of heparin oligosaccharide microarrays and surface plasmon resonance. Our results suggest that interactions between sulfated GAGs and parasite surface antigens contribute to T. gondii attachment to host cell surfaces as well as initiating the invasion process, while rhoptries and dense granule organelles may play an important role during the establishment of the infection and during the life of the parasite inside the parasitophorous vacuole. |
Schwartz, Tal ; Hutchison, James A; Leonard, Jeremie ; Genet, Cyriaque ; Haacke, Stefan ; Ebbesen, Thomas W Polariton Dynamics under Strong Light-Molecule Coupling Journal Article In: CHEMPHYSCHEM, 14 (1), pp. 125–131, 2013, ISSN: 1439-4235. @article{schwartz_polariton_2013, title = {Polariton Dynamics under Strong Light-Molecule Coupling}, author = {Schwartz, Tal and Hutchison, James A. and Leonard, Jeremie and Genet, Cyriaque and Haacke, Stefan and Ebbesen, Thomas W.}, doi = {10.1002/cphc.201200734}, issn = {1439-4235}, year = {2013}, date = {2013-01-01}, journal = {CHEMPHYSCHEM}, volume = {14}, number = {1}, pages = {125--131}, abstract = {We present a comprehensive experimental study of the photophysical properties of a moleculecavity system under strong coupling conditions, using steady-state and femtosecond time-resolved emission and absorption techniques to selectively excite the lower and upper polaritons as well as the reservoir of uncoupled molecules. Our results demonstrate the complex decay routes in such hybrid systems and that, contrary to expectations, the lower polariton is intrinsically long-lived.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We present a comprehensive experimental study of the photophysical properties of a moleculecavity system under strong coupling conditions, using steady-state and femtosecond time-resolved emission and absorption techniques to selectively excite the lower and upper polaritons as well as the reservoir of uncoupled molecules. Our results demonstrate the complex decay routes in such hybrid systems and that, contrary to expectations, the lower polariton is intrinsically long-lived. |
2012 |
Wilhelms, Nadine ; Kulchat, Sirinan ; Lehn, Jean-Marie Organocatalysis of C=N/C=N and C=C/C=N Exchange in Dynamic Covalent Chemistry Journal Article In: HELVETICA CHIMICA ACTA, 95 (12), pp. 2635–2651, 2012, ISSN: 0018-019X. @article{wilhelms_organocatalysis_2012, title = {Organocatalysis of C=N/C=N and C=C/C=N Exchange in Dynamic Covalent Chemistry}, author = {Wilhelms, Nadine and Kulchat, Sirinan and Lehn, Jean-Marie}, doi = {10.1002/hlca.201200515}, issn = {0018-019X}, year = {2012}, date = {2012-12-01}, journal = {HELVETICA CHIMICA ACTA}, volume = {95}, number = {12}, pages = {2635--2651}, abstract = {The reversibly formed C?N bond plays a very important role in dynamic covalent chemistry and the C?N/C?N exchange of components between different imine constituents to create dynamic covalent libraries has been extensively used. To facilitate diversity generation, we have investigated an organocatalyzed approach, using L-proline as catalyst, to accelerate the formation of dynamic libraries of [nxn] imine components. The organocatalysis methodology has also been extended, under somewhat modified conditions, to reversible C?C/C?N exchange processes between Knoevenagel derivatives of barbituric acid and imines, allowing for the generation of increased diversity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The reversibly formed C?N bond plays a very important role in dynamic covalent chemistry and the C?N/C?N exchange of components between different imine constituents to create dynamic covalent libraries has been extensively used. To facilitate diversity generation, we have investigated an organocatalyzed approach, using L-proline as catalyst, to accelerate the formation of dynamic libraries of [nxn] imine components. The organocatalysis methodology has also been extended, under somewhat modified conditions, to reversible C?C/C?N exchange processes between Knoevenagel derivatives of barbituric acid and imines, allowing for the generation of increased diversity. |
Martynov, Alexander G; Gorbunova, Yulia G; Nefedov, Sergey E; Tsivadze, Aslan Y; Sauvage, Jean-Pierre Synthesis and Copper(I)-Driven Disaggregation of a Zinc-Complexed Phthalocyanine Bearing Four Lateral Coordinating Rings Journal Article In: EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, (35), pp. 6888–6894, 2012, ISSN: 1434-193X. @article{martynov_synthesis_2012, title = {Synthesis and Copper(I)-Driven Disaggregation of a Zinc-Complexed Phthalocyanine Bearing Four Lateral Coordinating Rings}, author = {Martynov, Alexander G. and Gorbunova, Yulia G. and Nefedov, Sergey E. and Tsivadze, Aslan Y. and Sauvage, Jean-Pierre}, doi = {10.1002/ejoc.201200944}, issn = {1434-193X}, year = {2012}, date = {2012-12-01}, journal = {EUROPEAN JOURNAL OF ORGANIC CHEMISTRY}, number = {35}, pages = {6888--6894}, abstract = {A new zinc phthalocyaninate, bearing four flexible phenanthroline-containing 30-membered rings was synthesized by template condensation of a macrocyclic phthalonitrile. The resulting phthalocyanine was an insoluble aggregate. However, in the presence of Cu-I ions, the formation of a soluble complex was observed. UV/Vis and DOSY NMR spectroscopic studies showed a monomolecular state for this species in solution. H-1-H-1 ROESY demonstrated that the macrocyclic substituents adopt a folded conformation, giving the complex a globular shape. The folding originates from stacking interactions between the phthalocyanine core and peripheral copper(I)-phenanthroline complexes.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A new zinc phthalocyaninate, bearing four flexible phenanthroline-containing 30-membered rings was synthesized by template condensation of a macrocyclic phthalonitrile. The resulting phthalocyanine was an insoluble aggregate. However, in the presence of Cu-I ions, the formation of a soluble complex was observed. UV/Vis and DOSY NMR spectroscopic studies showed a monomolecular state for this species in solution. H-1-H-1 ROESY demonstrated that the macrocyclic substituents adopt a folded conformation, giving the complex a globular shape. The folding originates from stacking interactions between the phthalocyanine core and peripheral copper(I)-phenanthroline complexes. |
Caballero, David ; Osmani, Nael ; Georges-Labouesse, Elisabeth ; Labouesse, Michel ; Riveline, Daniel Separation of distinct adhesion complexes and associated cytoskeleton by a micro-stencil-printing method Journal Article In: CELL ADHESION & MIGRATION, 6 (6), pp. 471–475, 2012, ISSN: 1933-6918. @article{caballero_separation_2012, title = {Separation of distinct adhesion complexes and associated cytoskeleton by a micro-stencil-printing method}, author = {Caballero, David and Osmani, Nael and Georges-Labouesse, Elisabeth and Labouesse, Michel and Riveline, Daniel}, doi = {10.4161/cam.22198}, issn = {1933-6918}, year = {2012}, date = {2012-12-01}, journal = {CELL ADHESION & MIGRATION}, volume = {6}, number = {6}, pages = {471--475}, abstract = {Adhesion between cells and the extracellular matrix is mediated by different types of transmembraneous proteins. Their associations to specific partners lead to the assembly of contacts such as focal adhesions and hemidesmosomes. The spatial overlap between both contacts within cells has however limited the study of each type of contact. Here we show that with “stampcils” focal contacts and hemidesmosomes can be spatially separated: cells are plated within the cavities of a stencil and the grids of the stencil serve as stamps for grafting an extracellular matrix protein-fibronectin. Cells engage new contacts on stamped zones leading to the segregation of adhesions and their associated cytoskeletons, i.e., actin and intermediate filaments of keratins. This new method should provide new insights into cell contacts compositions and dynamics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Adhesion between cells and the extracellular matrix is mediated by different types of transmembraneous proteins. Their associations to specific partners lead to the assembly of contacts such as focal adhesions and hemidesmosomes. The spatial overlap between both contacts within cells has however limited the study of each type of contact. Here we show that with “stampcils” focal contacts and hemidesmosomes can be spatially separated: cells are plated within the cavities of a stencil and the grids of the stencil serve as stamps for grafting an extracellular matrix protein-fibronectin. Cells engage new contacts on stamped zones leading to the segregation of adhesions and their associated cytoskeletons, i.e., actin and intermediate filaments of keratins. This new method should provide new insights into cell contacts compositions and dynamics. |
Cho, Eun Seon ; Kim, Jiwon ; Tejerina, Baudilio ; Hermans, Thomas M; Jiang, Hao ; Nakanishi, Hideyuki ; Yu, Miao ; Patashinski, Alexander Z; Glotzer, Sharon C; Stellacci, Francesco ; Grzybowski, Bartosz A Ultrasensitive detection of toxic cations through changes in the tunnelling current across films of striped nanoparticles Journal Article In: NATURE MATERIALS, 11 (11), pp. 978–985, 2012, ISSN: 1476-1122. @article{cho_ultrasensitive_2012, title = {Ultrasensitive detection of toxic cations through changes in the tunnelling current across films of striped nanoparticles}, author = {Cho, Eun Seon and Kim, Jiwon and Tejerina, Baudilio and Hermans, Thomas M. and Jiang, Hao and Nakanishi, Hideyuki and Yu, Miao and Patashinski, Alexander Z. and Glotzer, Sharon C. and Stellacci, Francesco and Grzybowski, Bartosz A.}, doi = {10.1038/NMAT3406}, issn = {1476-1122}, year = {2012}, date = {2012-11-01}, journal = {NATURE MATERIALS}, volume = {11}, number = {11}, pages = {978--985}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Hahn, Uwe ; Luelf, Henning ; Winkler, Henrik D F; Schalley, Christoph A; Voegtle, Fritz ; De Cola, Luisa Encapsulation of Luminescent Homoleptic [Ru(dpp)3]2+-Type Chromophores within an Amphiphilic Dendritic Environment Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 18 (48), pp. 15424–15432, 2012, ISSN: 0947-6539. @article{hahn_encapsulation_2012, title = {Encapsulation of Luminescent Homoleptic [Ru(dpp)3]2+-Type Chromophores within an Amphiphilic Dendritic Environment}, author = {Hahn, Uwe and Luelf, Henning and Winkler, Henrik D. F. and Schalley, Christoph A. and Voegtle, Fritz and De Cola, Luisa}, doi = {10.1002/chem.201201126}, issn = {0947-6539}, year = {2012}, date = {2012-11-01}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {18}, number = {48}, pages = {15424--15432}, abstract = {A new series of homoleptic metallodendrimers has been synthesized through ruthenium-metal complexation by dendritically modified bathophenanthroline ligands. The presence of hydrophilic oligo(ethylene glycol) groups on the surface of the monodisperse metal complexes enabled the solubilization of all of the fractal species in a wide range of solvents, including water. The specific properties of all of these compounds have been systematically investigated by using photophysical techniques as a function of the generation number. Accordingly, the encapsulation of the highly luminescent [Ru(dpp)3]2+-type (dpp=4,7-diphenyl-1,10-phenanthroline) core unit within a dendritic microenvironment creates a powerful means to shield the center from dioxygen quenching. This shielding effect, as exerted on the phosphorescent ruthenium-derived center, is reflected by enhanced emission intensities and extended excited-state lifetimes that are close to the highest values reported so far, even in an air-equilibrated aqueous medium. Interestingly, when inspecting the largest dendritic assembly, that is, the third-generation assembly, significant drops in emission quantum yields and lifetimes are observed. This anomalous behavior has been attributed to the folding of the branches towards the luminescent core.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A new series of homoleptic metallodendrimers has been synthesized through ruthenium-metal complexation by dendritically modified bathophenanthroline ligands. The presence of hydrophilic oligo(ethylene glycol) groups on the surface of the monodisperse metal complexes enabled the solubilization of all of the fractal species in a wide range of solvents, including water. The specific properties of all of these compounds have been systematically investigated by using photophysical techniques as a function of the generation number. Accordingly, the encapsulation of the highly luminescent [Ru(dpp)3]2+-type (dpp=4,7-diphenyl-1,10-phenanthroline) core unit within a dendritic microenvironment creates a powerful means to shield the center from dioxygen quenching. This shielding effect, as exerted on the phosphorescent ruthenium-derived center, is reflected by enhanced emission intensities and extended excited-state lifetimes that are close to the highest values reported so far, even in an air-equilibrated aqueous medium. Interestingly, when inspecting the largest dendritic assembly, that is, the third-generation assembly, significant drops in emission quantum yields and lifetimes are observed. This anomalous behavior has been attributed to the folding of the branches towards the luminescent core. |
Gorodetski, Yuri ; Lombard, Emmanuel ; Drezet, Aurelien ; Genet, Cyriaque ; Ebbesen, Thomas W A perfect plasmonic quarter-wave plate Journal Article In: APPLIED PHYSICS LETTERS, 101 (20), 2012, ISSN: 0003-6951. @article{gorodetski_perfect_2012, title = {A perfect plasmonic quarter-wave plate}, author = {Gorodetski, Yuri and Lombard, Emmanuel and Drezet, Aurelien and Genet, Cyriaque and Ebbesen, Thomas W.}, doi = {10.1063/1.4766189}, issn = {0003-6951}, year = {2012}, date = {2012-11-01}, journal = {APPLIED PHYSICS LETTERS}, volume = {101}, number = {20}, abstract = {The excitation of surface plasmons on an elliptical grating followed by the transmission through a subwavelength aperture can modify the polarization state of the incoming light. The combined effect of the elliptical grooves and a slightly elliptical central hole allows to fully control the birefringence and retardation of the structure, providing a simple approach for polarization state design by the geometry of the structure. From this combination, a perfect plasmonic quarter-wave plate is obtained. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4766189]}, keywords = {}, pubstate = {published}, tppubtype = {article} } The excitation of surface plasmons on an elliptical grating followed by the transmission through a subwavelength aperture can modify the polarization state of the incoming light. The combined effect of the elliptical grooves and a slightly elliptical central hole allows to fully control the birefringence and retardation of the structure, providing a simple approach for polarization state design by the geometry of the structure. From this combination, a perfect plasmonic quarter-wave plate is obtained. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4766189] |
Lazzerini, G M; Mian, S; Di Stasio, F; Masillamani, Merari A; Crivillers, N; Reinders, F; Mayor, M; Samori, P; Cacialli, F Increased efficiency of light-emitting diodes incorporating anodes functionalized with fluorinated azobenzene monolayers and a green-emitting polyfluorene derivative Journal Article In: APPLIED PHYSICS LETTERS, 101 (15), 2012, ISSN: 0003-6951. @article{lazzerini_increased_2012, title = {Increased efficiency of light-emitting diodes incorporating anodes functionalized with fluorinated azobenzene monolayers and a green-emitting polyfluorene derivative}, author = {Lazzerini, G. M. and Mian, S. and Di Stasio, F. and Masillamani, A. Merari and Crivillers, N. and Reinders, F. and Mayor, M. and Samori, P. and Cacialli, F.}, doi = {10.1063/1.4758682}, issn = {0003-6951}, year = {2012}, date = {2012-10-01}, journal = {APPLIED PHYSICS LETTERS}, volume = {101}, number = {15}, abstract = {We investigate the functionalization of gold anodes with azobenzene-based self-assembled monolayers (AZO-SAM) and the influence of such functionalization on the external quantum efficiency (EQE) of polyfluorene-based light-emitting diodes (LEDs). Photoluminescence and electroluminescence measurements show that the AZO-SAMs do not modify the shape of the emission spectrum of the active layer. Instead, AZO-SAMs enhance the EQE of LEDs by an order of magnitude (from 0.018% to 0.18%) and decrease the turn-on voltage from 7.9 V to 6.2 V by reducing the injection barrier at the anode, thus promoting a better balance between hole and electron populations in the active layer. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4758682]}, keywords = {}, pubstate = {published}, tppubtype = {article} } We investigate the functionalization of gold anodes with azobenzene-based self-assembled monolayers (AZO-SAM) and the influence of such functionalization on the external quantum efficiency (EQE) of polyfluorene-based light-emitting diodes (LEDs). Photoluminescence and electroluminescence measurements show that the AZO-SAMs do not modify the shape of the emission spectrum of the active layer. Instead, AZO-SAMs enhance the EQE of LEDs by an order of magnitude (from 0.018% to 0.18%) and decrease the turn-on voltage from 7.9 V to 6.2 V by reducing the injection barrier at the anode, thus promoting a better balance between hole and electron populations in the active layer. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4758682] |
Gomez, Jean-Pierre ; Jaffres, Paul-Alain ; Cheradame, Herve ; Guegan, Philippe ; Pitard, Bruno ; Lehn, Pierre ; Pichon, Chantal ; Midoux, Patrick Trans-endothelial passage of chemical vectors in a skeletal muscle endothelium model: Effect of inflammatory cytokines. Journal Article In: HUMAN GENE THERAPY, 23 (10), pp. A140, 2012, ISSN: 1043-0342. @article{gomez_trans-endothelial_2012, title = {Trans-endothelial passage of chemical vectors in a skeletal muscle endothelium model: Effect of inflammatory cytokines.}, author = {Gomez, Jean-Pierre and Jaffres, Paul-Alain and Cheradame, Herve and Guegan, Philippe and Pitard, Bruno and Lehn, Pierre and Pichon, Chantal and Midoux, Patrick}, issn = {1043-0342}, year = {2012}, date = {2012-10-01}, journal = {HUMAN GENE THERAPY}, volume = {23}, number = {10}, pages = {A140}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Glaetzle, A W; Nath, R; Zhao, B; Pupillo, G; Zoller, P Driven-dissipative dynamics of a strongly interacting Rydberg gas Journal Article In: PHYSICAL REVIEW A, 86 (4), 2012, ISSN: 1050-2947. @article{glaetzle_driven-dissipative_2012, title = {Driven-dissipative dynamics of a strongly interacting Rydberg gas}, author = {Glaetzle, A. W. and Nath, R. and Zhao, B. and Pupillo, G. and Zoller, P.}, doi = {10.1103/PhysRevA.86.043403}, issn = {1050-2947}, year = {2012}, date = {2012-10-01}, journal = {PHYSICAL REVIEW A}, volume = {86}, number = {4}, abstract = {We study the nonequilibrium many-body dynamics of a cold gas of ground-state alkali-metal atoms weakly admixed by Rydberg states with laser light. On a time scale shorter than the lifetime of the dressed states, effective dipole-dipole or van der Waals interactions between atoms can lead to the formation of strongly correlated phases, such as atomic crystals. Using a semiclassical approach, we study the long-time dynamics where decoherence and dissipative processes due to spontaneous emission and blackbody radiation dominate, leading to heating and melting of atomic crystals as well as particle losses. These effects can be substantially mitigated by performing active laser cooling in the presence of atomic dressing.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We study the nonequilibrium many-body dynamics of a cold gas of ground-state alkali-metal atoms weakly admixed by Rydberg states with laser light. On a time scale shorter than the lifetime of the dressed states, effective dipole-dipole or van der Waals interactions between atoms can lead to the formation of strongly correlated phases, such as atomic crystals. Using a semiclassical approach, we study the long-time dynamics where decoherence and dissipative processes due to spontaneous emission and blackbody radiation dominate, leading to heating and melting of atomic crystals as well as particle losses. These effects can be substantially mitigated by performing active laser cooling in the presence of atomic dressing. |
Baranov, M A; Dalmonte, M; Pupillo, G; Zoller, P Condensed Matter Theory of Dipolar Quantum Gases Journal Article In: CHEMICAL REVIEWS, 112 (9, SI), pp. 5012–5061, 2012, ISSN: 0009-2665. @article{baranov_condensed_2012, title = {Condensed Matter Theory of Dipolar Quantum Gases}, author = {Baranov, M. A. and Dalmonte, M. and Pupillo, G. and Zoller, P.}, doi = {10.1021/cr2003568}, issn = {0009-2665}, year = {2012}, date = {2012-09-01}, journal = {CHEMICAL REVIEWS}, volume = {112}, number = {9, SI}, pages = {5012--5061}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Mohankumar, Meera ; Holler, Michel ; Nierengarten, Jean-Francois ; Sauvage, Jean-Pierre Preparation of Copper(I) Pseudo-rotaxanes from Bis-phosphine Ligands Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 18 (39), pp. 12192–12195, 2012, ISSN: 0947-6539. @article{mohankumar_preparation_2012, title = {Preparation of Copper(I) Pseudo-rotaxanes from Bis-phosphine Ligands}, author = {Mohankumar, Meera and Holler, Michel and Nierengarten, Jean-Francois and Sauvage, Jean-Pierre}, doi = {10.1002/chem.201202170}, issn = {0947-6539}, year = {2012}, date = {2012-09-01}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {18}, number = {39}, pages = {12192--12195}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Guenet, Aurelie ; Eckes, Fabrice ; Bulach, Veronique ; Strassert, Cristian A; De Cola, Luisa ; Hosseini, Mir Wais Sensitisation of the Near-Infrared Emission of NdIII from the Singlet State of Porphyrins Bearing Four 8-Hydroxyquinolinylamide Chelates Journal Article In: CHEMPHYSCHEM, 13 (13), pp. 3163–3171, 2012, ISSN: 1439-4235. @article{guenet_sensitisation_2012, title = {Sensitisation of the Near-Infrared Emission of NdIII from the Singlet State of Porphyrins Bearing Four 8-Hydroxyquinolinylamide Chelates}, author = {Guenet, Aurelie and Eckes, Fabrice and Bulach, Veronique and Strassert, Cristian A. and De Cola, Luisa and Hosseini, Mir Wais}, doi = {10.1002/cphc.201200328}, issn = {1439-4235}, year = {2012}, date = {2012-09-01}, journal = {CHEMPHYSCHEM}, volume = {13}, number = {13}, pages = {3163--3171}, abstract = {The a4 atropoisomer of a tetraaryl porphyrin and its PdII complex, both bearing four hydroxyquinolinyl chelating units pre-organised on the same face of the porphyrin backbone, bind a NdIII centre thus affording either a mononuclear or a heterobinuclear anionic species, respectively. The near-infrared emission of the lanthanide centred at 1064 nm is observed upon excitation of the Soret band at 425 nm. Sensitisation proceeds mainly from the singlet state of the porphyrin.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The a4 atropoisomer of a tetraaryl porphyrin and its PdII complex, both bearing four hydroxyquinolinyl chelating units pre-organised on the same face of the porphyrin backbone, bind a NdIII centre thus affording either a mononuclear or a heterobinuclear anionic species, respectively. The near-infrared emission of the lanthanide centred at 1064 nm is observed upon excitation of the Soret band at 425 nm. Sensitisation proceeds mainly from the singlet state of the porphyrin. |
Masillamani, Appan Merari ; Crivillers, Nuria ; Orgiu, Emanuele ; Rotzler, Juergen ; Bossert, David ; Thippeswamy, Ramakrishnappa ; Zharnikov, Michael ; Mayor, Marcel ; Samori, Paolo Multiscale Charge Injection and Transport Properties in Self-Assembled Monolayers of Biphenyl Thiols with Varying Torsion Angles Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 18 (33), pp. 10335–10347, 2012, ISSN: 0947-6539. @article{masillamani_multiscale_2012, title = {Multiscale Charge Injection and Transport Properties in Self-Assembled Monolayers of Biphenyl Thiols with Varying Torsion Angles}, author = {Masillamani, Appan Merari and Crivillers, Nuria and Orgiu, Emanuele and Rotzler, Juergen and Bossert, David and Thippeswamy, Ramakrishnappa and Zharnikov, Michael and Mayor, Marcel and Samori, Paolo}, doi = {10.1002/chem.201201858}, issn = {0947-6539}, year = {2012}, date = {2012-08-01}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {18}, number = {33}, pages = {10335--10347}, abstract = {This article describes the molecular structurefunction relationship for a series of biphenylthiol derivatives with varying torsional degree of freedom in their molecular backbone when self-assembled on gold electrodes. These biphenylthiol molecules chemisorbed on Au exhibit different tilt angles with respect to the surface normal and different packing densities. The charge transport through the biphenylthiol self-assembled monolayers (SAMs) showed a characteristic decay trend with the effective monolayer thickness. Based on parallel pathways model the tunneling decay factor beta was estimated to be 0.27 angstrom-1. The hole mobility of poly(3-hexylthiophene)-based thin-film transistors incorporating a biphenylthiol SAM coating the Au source and drain electrodes revealed a dependence on the injection barrier with the highest occupied molecular orbital (HOMO) level of the semiconductor. The possible role of the resistivity of the SAMs on transistor electrodes on the threshold voltage shift is discussed. The control over the chemical structure, electronic properties, and packing order of the SAMs provides a versatile platform to regulate the charge injection in organic electronic devices.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This article describes the molecular structurefunction relationship for a series of biphenylthiol derivatives with varying torsional degree of freedom in their molecular backbone when self-assembled on gold electrodes. These biphenylthiol molecules chemisorbed on Au exhibit different tilt angles with respect to the surface normal and different packing densities. The charge transport through the biphenylthiol self-assembled monolayers (SAMs) showed a characteristic decay trend with the effective monolayer thickness. Based on parallel pathways model the tunneling decay factor beta was estimated to be 0.27 angstrom-1. The hole mobility of poly(3-hexylthiophene)-based thin-film transistors incorporating a biphenylthiol SAM coating the Au source and drain electrodes revealed a dependence on the injection barrier with the highest occupied molecular orbital (HOMO) level of the semiconductor. The possible role of the resistivity of the SAMs on transistor electrodes on the threshold voltage shift is discussed. The control over the chemical structure, electronic properties, and packing order of the SAMs provides a versatile platform to regulate the charge injection in organic electronic devices. |
Orgiu, Emanuele ; Crivillers, Nuria ; Herder, Martin ; Grubert, Lutz ; Paetzel, Michael ; Frisch, Johannes ; Pavlica, Egon ; Duong, Duc T; Bratina, Gvido ; Salleo, Alberto ; Koch, Norbert ; Hecht, Stefan ; Samori, Paolo Optically switchable transistor via energy-level phototuning in a bicomponent organic semiconductor Journal Article In: NATURE CHEMISTRY, 4 (8), pp. 675–679, 2012, ISSN: 1755-4330. @article{orgiu_optically_2012, title = {Optically switchable transistor via energy-level phototuning in a bicomponent organic semiconductor}, author = {Orgiu, Emanuele and Crivillers, Nuria and Herder, Martin and Grubert, Lutz and Paetzel, Michael and Frisch, Johannes and Pavlica, Egon and Duong, Duc T. and Bratina, Gvido and Salleo, Alberto and Koch, Norbert and Hecht, Stefan and Samori, Paolo}, doi = {10.1038/NCHEM.1384}, issn = {1755-4330}, year = {2012}, date = {2012-08-01}, journal = {NATURE CHEMISTRY}, volume = {4}, number = {8}, pages = {675--679}, abstract = {Organic semiconductors are suitable candidates for printable, flexible and large-area electronics. Alongside attaining an improved device performance, to confer a multifunctional nature to the employed materials is key for organic-based logic applications. Here we report on the engineering of an electronic structure in a semiconducting film by blending two molecular components, a photochromic diarylethene derivative and a poly(3-hexylthiophene) (P3HT) matrix, to attain phototunable and bistable energy levels for the P3HT's hole transport. As a proof-of-concept we exploited this blend as a semiconducting material in organic thin-film transistors. The device illumination at defined wavelengths enabled reversible tuning of the diarylethene's electronic states in the blend, which resulted in modulation of the output current. The device photoresponse was found to be in the microsecond range, and thus on a technologically relevant timescale. This modular blending approach allows for the convenient incorporation of various molecular components, which opens up perspectives on multifunctional devices and logic circuits.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Organic semiconductors are suitable candidates for printable, flexible and large-area electronics. Alongside attaining an improved device performance, to confer a multifunctional nature to the employed materials is key for organic-based logic applications. Here we report on the engineering of an electronic structure in a semiconducting film by blending two molecular components, a photochromic diarylethene derivative and a poly(3-hexylthiophene) (P3HT) matrix, to attain phototunable and bistable energy levels for the P3HT's hole transport. As a proof-of-concept we exploited this blend as a semiconducting material in organic thin-film transistors. The device illumination at defined wavelengths enabled reversible tuning of the diarylethene's electronic states in the blend, which resulted in modulation of the output current. The device photoresponse was found to be in the microsecond range, and thus on a technologically relevant timescale. This modular blending approach allows for the convenient incorporation of various molecular components, which opens up perspectives on multifunctional devices and logic circuits. |
Hafezi, Nema ; Lehn, Jean-Marie Adaptation of Dynamic Covalent Systems of Imine Constituents to Medium Change by Component Redistribution under Reversible Phase Separation Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 134 (30), pp. 12861–12868, 2012, ISSN: 0002-7863. @article{hafezi_adaptation_2012, title = {Adaptation of Dynamic Covalent Systems of Imine Constituents to Medium Change by Component Redistribution under Reversible Phase Separation}, author = {Hafezi, Nema and Lehn, Jean-Marie}, doi = {10.1021/ja305379c}, issn = {0002-7863}, year = {2012}, date = {2012-08-01}, journal = {JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, volume = {134}, number = {30}, pages = {12861--12868}, abstract = {A dynamic covalent library of interconverting imine constituents, dissolved in an acetonitrile/water mixture, undergoes constitutional reorganization upon phase separation induced by a physical stimulus (heat) or a chemical effector (inorganic salt, carbohydrate, organic solvent). The process has been made reversible, regenerating the initial library upon phase reunification. It represents the behavior of a dynamic covalent library upon reversible phase separation and its adaptation to a phase change, with up-regulation in each phase of-the fittest constituents by component selection. Finally, the system exemplifies the splitting of a 2D (square) constitutional dynamic network into a 3D (cube) one.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A dynamic covalent library of interconverting imine constituents, dissolved in an acetonitrile/water mixture, undergoes constitutional reorganization upon phase separation induced by a physical stimulus (heat) or a chemical effector (inorganic salt, carbohydrate, organic solvent). The process has been made reversible, regenerating the initial library upon phase reunification. It represents the behavior of a dynamic covalent library upon reversible phase separation and its adaptation to a phase change, with up-regulation in each phase of-the fittest constituents by component selection. Finally, the system exemplifies the splitting of a 2D (square) constitutional dynamic network into a 3D (cube) one. |
Boyle, Megan M; Gassensmith, Jeremiah J; Whalley, Adam C; Forgan, Ross S; Smaldone, Ronald A; Hartlieb, Karel J; Blackburn, Anthea K; Sauvage, Jean-Pierre ; Stoddart, Fraser J Stereochemistry of Molecular Figures-of-Eight Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 18 (33), pp. 10312–10323, 2012, ISSN: 0947-6539. @article{boyle_stereochemistry_2012, title = {Stereochemistry of Molecular Figures-of-Eight}, author = {Boyle, Megan M. and Gassensmith, Jeremiah J. and Whalley, Adam C. and Forgan, Ross S. and Smaldone, Ronald A. and Hartlieb, Karel J. and Blackburn, Anthea K. and Sauvage, Jean-Pierre and Stoddart, J. Fraser}, doi = {10.1002/chem.201202070}, issn = {0947-6539}, year = {2012}, date = {2012-08-01}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {18}, number = {33}, pages = {10312--10323}, abstract = {A trans isomer of a figure-of-eight (Fo8) compound was prepared from an electron-withdrawing cyclobis(paraquat-p-phenylene) derivative carrying trans-disposed azide functions between its two phenylene rings. Copper(I)-catalyzed azidealkyne cycloadditions with a bispropargyl derivative of a polyether chain, interrupted in its midriff by an electron-donating 1,5-dioxynaphthalene unit acting as the template to organize the reactants prior to the onset of two click reactions, afforded the Fo8 compound with Ci symmetry. Exactly the same chemistry is performed on the cis-bisazide of the tetracationic cyclophane to give a Fo8 compound with C2 symmetry. Both of these Fo8 compounds exist as major and very minor conformational isomers in solution. The major conformation in the trans series, which has been characterized by X-ray crystallography, adopts a geometry which maximizes its C?H...O interactions, while maintaining its p...p stacking and C?H...p interactions. Ab initio calculations at the M06L level support the conformational assignments to the major and minor isomers in the trans series. Dynamic 1H NMR spectroscopy, supported by 2D 1H NMR experiments, indicates that the major and minor isomers in both the cis and trans series equilibrate in solution on the 1H NMR timescale rapidly above and slowly below room temperature.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A trans isomer of a figure-of-eight (Fo8) compound was prepared from an electron-withdrawing cyclobis(paraquat-p-phenylene) derivative carrying trans-disposed azide functions between its two phenylene rings. Copper(I)-catalyzed azidealkyne cycloadditions with a bispropargyl derivative of a polyether chain, interrupted in its midriff by an electron-donating 1,5-dioxynaphthalene unit acting as the template to organize the reactants prior to the onset of two click reactions, afforded the Fo8 compound with Ci symmetry. Exactly the same chemistry is performed on the cis-bisazide of the tetracationic cyclophane to give a Fo8 compound with C2 symmetry. Both of these Fo8 compounds exist as major and very minor conformational isomers in solution. The major conformation in the trans series, which has been characterized by X-ray crystallography, adopts a geometry which maximizes its C?H...O interactions, while maintaining its p...p stacking and C?H...p interactions. Ab initio calculations at the M06L level support the conformational assignments to the major and minor isomers in the trans series. Dynamic 1H NMR spectroscopy, supported by 2D 1H NMR experiments, indicates that the major and minor isomers in both the cis and trans series equilibrate in solution on the 1H NMR timescale rapidly above and slowly below room temperature. |
Cuche, A; Stein, B; Canaguier-Durand, A; Devaux, E; Genet, C; Ebbesen, T W Brownian Motion in a Designer Force Field: Dynamical Effects of Negative Refraction on Nanoparticles Journal Article In: NANO LETTERS, 12 (8), pp. 4329–4332, 2012, ISSN: 1530-6984. @article{cuche_brownian_2012, title = {Brownian Motion in a Designer Force Field: Dynamical Effects of Negative Refraction on Nanoparticles}, author = {Cuche, A. and Stein, B. and Canaguier-Durand, A. and Devaux, E. and Genet, C. and Ebbesen, T. W.}, doi = {10.1021/nl302060t}, issn = {1530-6984}, year = {2012}, date = {2012-08-01}, journal = {NANO LETTERS}, volume = {12}, number = {8}, pages = {4329--4332}, abstract = {Photonic crystals (PC) have demonstrated unique features that have renewed the fields of classical and quantum optics. Although holding great promises, associated mechanical effects have proven challenging to observe. We demonstrate for the first time that one of the most salient properties of PC, namely negative refraction, can induce specific forces on metal nanoparticles. By integrating a periodically patterned metal film in a fluidic cell, we show that near-field optical forces associated with negatively refracted surface plasmons are capable of controlling particle trajectories. Coupling particle motions to PC band structures draws new approaches and strategies for parallel and high resolution all-optical control of particle flows with applications for micro- and nanofluidic systems.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Photonic crystals (PC) have demonstrated unique features that have renewed the fields of classical and quantum optics. Although holding great promises, associated mechanical effects have proven challenging to observe. We demonstrate for the first time that one of the most salient properties of PC, namely negative refraction, can induce specific forces on metal nanoparticles. By integrating a periodically patterned metal film in a fluidic cell, we show that near-field optical forces associated with negatively refracted surface plasmons are capable of controlling particle trajectories. Coupling particle motions to PC band structures draws new approaches and strategies for parallel and high resolution all-optical control of particle flows with applications for micro- and nanofluidic systems. |
Raimondo, Corinna ; Crivillers, Nuria ; Reinders, Federica ; Sander, Fabian ; Mayor, Marcel ; Samori, Paolo Optically switchable organic field-effect transistors based on photoresponsive gold nanoparticles blended with poly(3-hexylthiophene) Journal Article In: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 109 (31), pp. 12375–12380, 2012, ISSN: 0027-8424. @article{raimondo_optically_2012, title = {Optically switchable organic field-effect transistors based on photoresponsive gold nanoparticles blended with poly(3-hexylthiophene)}, author = {Raimondo, Corinna and Crivillers, Nuria and Reinders, Federica and Sander, Fabian and Mayor, Marcel and Samori, Paolo}, doi = {10.1073/pnas.1203848109}, issn = {0027-8424}, year = {2012}, date = {2012-07-01}, journal = {PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, volume = {109}, number = {31}, pages = {12375--12380}, abstract = {Interface tailoring represents a route for integrating complex functions in systems and materials. Although it is ubiquitous in biological systems-e.g., in membranes-synthetic attempts have not yet reached the same level of sophistication. Here, we report on the fabrication of an organic field-effect transistor featuring dual-gate response. Alongside the electric control through the gate electrode, we incorporated photoresponsive nanostructures in the polymeric semiconductor via blending, thereby providing optical switching ability to the device. In particular, we mixed poly(3-hexylthiophene) with gold nanoparticles (AuNP) coated with a chemisorbed azobenzene-based self-assembled monolayer, acting as traps for the charges in the device. The light-induced isomerization between the trans and cis states of the azobenzene molecules coating the AuNP induces a variation of the tunneling barrier, which controls the efficiency of the charge trapping/detrapping process within the semiconducting film. Our approach offers unique solutions to digital commuting between optical and electric signals.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Interface tailoring represents a route for integrating complex functions in systems and materials. Although it is ubiquitous in biological systems-e.g., in membranes-synthetic attempts have not yet reached the same level of sophistication. Here, we report on the fabrication of an organic field-effect transistor featuring dual-gate response. Alongside the electric control through the gate electrode, we incorporated photoresponsive nanostructures in the polymeric semiconductor via blending, thereby providing optical switching ability to the device. In particular, we mixed poly(3-hexylthiophene) with gold nanoparticles (AuNP) coated with a chemisorbed azobenzene-based self-assembled monolayer, acting as traps for the charges in the device. The light-induced isomerization between the trans and cis states of the azobenzene molecules coating the AuNP induces a variation of the tunneling barrier, which controls the efficiency of the charge trapping/detrapping process within the semiconducting film. Our approach offers unique solutions to digital commuting between optical and electric signals. |
Ovchinnikov, Victor ; Karplus, Martin Analysis and Elimination of a Bias in Targeted Molecular Dynamics Simulations of Conformational Transitions: Application to Calmodulin Journal Article In: JOURNAL OF PHYSICAL CHEMISTRY B, 116 (29, SI), pp. 8584–8603, 2012, ISSN: 1520-6106. @article{ovchinnikov_analysis_2012, title = {Analysis and Elimination of a Bias in Targeted Molecular Dynamics Simulations of Conformational Transitions: Application to Calmodulin}, author = {Ovchinnikov, Victor and Karplus, Martin}, doi = {10.1021/jp212634z}, issn = {1520-6106}, year = {2012}, date = {2012-07-01}, journal = {JOURNAL OF PHYSICAL CHEMISTRY B}, volume = {116}, number = {29, SI}, pages = {8584--8603}, abstract = {The popular targeted molecular dynamics (TMD) method for generating transition paths in complex biomolecular systems is revisited. In a typical TMD transition path, the large-scale changes occur early and the small-scale changes tend to occur later. As a result, the order of events in the computed paths depends on the direction in which the simulations are performed. To identify the origin of this bias, and to propose a method in which the bias is absent, variants of TMD in the restraint formulation are introduced and applied to the complex open textbackslashtextbackslashtextless-textbackslashtextbackslashtextgreater closed transition in the protein calmodulin. Due to the global best-fit rotation that is typically part of the TMD method, the simulated system is guided implicitly along the lowest frequency normal modes, until the large spatial scales associated with these modes are near the target conformation. The remaining portion of the transition is described progressively by higher frequency modes, which correspond to smaller scale rearrangements. A straightforward modification of TMD that avoids the global best fit rotation is the locally restrained TMD (LRTMD) method, in which the biasing potential is constructed from a number of TMD potentials, each acting on a small connected portion of the protein sequence. With a uniform distribution of these elements, transition paths that lack the length scale bias are obtained. Trajectories generated by steered MD in dihedral angle space (DSMD), a Method that avoids best fit rotations altogether, also lack the length scale bias. To examine the importance of the paths generated by TMD, LRTMD, and DSMD in the actual transition, we use the finite temperature string method to compute the free energy profile associated with a transition tube around a path generated by each algorithm. The free energy barriers associated with the paths are comparable, suggesting that transitions can occur along each route with similar probabilities. This result indicates that a,broad ensemble of paths needs to be calculated to obtain a full description of conformational changes in biomolecules. The breadth of the contributing ensemble suggests that energetic barriers for conformational transitions in proteins are offset by entropic contributions that arise from a large number of possible paths.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The popular targeted molecular dynamics (TMD) method for generating transition paths in complex biomolecular systems is revisited. In a typical TMD transition path, the large-scale changes occur early and the small-scale changes tend to occur later. As a result, the order of events in the computed paths depends on the direction in which the simulations are performed. To identify the origin of this bias, and to propose a method in which the bias is absent, variants of TMD in the restraint formulation are introduced and applied to the complex open textbackslashtextbackslashtextless-textbackslashtextbackslashtextgreater closed transition in the protein calmodulin. Due to the global best-fit rotation that is typically part of the TMD method, the simulated system is guided implicitly along the lowest frequency normal modes, until the large spatial scales associated with these modes are near the target conformation. The remaining portion of the transition is described progressively by higher frequency modes, which correspond to smaller scale rearrangements. A straightforward modification of TMD that avoids the global best fit rotation is the locally restrained TMD (LRTMD) method, in which the biasing potential is constructed from a number of TMD potentials, each acting on a small connected portion of the protein sequence. With a uniform distribution of these elements, transition paths that lack the length scale bias are obtained. Trajectories generated by steered MD in dihedral angle space (DSMD), a Method that avoids best fit rotations altogether, also lack the length scale bias. To examine the importance of the paths generated by TMD, LRTMD, and DSMD in the actual transition, we use the finite temperature string method to compute the free energy profile associated with a transition tube around a path generated by each algorithm. The free energy barriers associated with the paths are comparable, suggesting that transitions can occur along each route with similar probabilities. This result indicates that a,broad ensemble of paths needs to be calculated to obtain a full description of conformational changes in biomolecules. The breadth of the contributing ensemble suggests that energetic barriers for conformational transitions in proteins are offset by entropic contributions that arise from a large number of possible paths. |
Crenshaw, Charisse M; Nam, Kwangho ; Oo, Kimberly ; Kutchukian, Peter S; Bowman, Brian R; Karplus, Martin ; Verdine, Gregory L Enforced Presentation of an Extrahelical Guanine to the Lesion Recognition Pocket of Human 8-Oxoguanine Glycosylase, hOGG1 Journal Article In: JOURNAL OF BIOLOGICAL CHEMISTRY, 287 (30), pp. 24916–24928, 2012, ISSN: 0021-9258. @article{crenshaw_enforced_2012, title = {Enforced Presentation of an Extrahelical Guanine to the Lesion Recognition Pocket of Human 8-Oxoguanine Glycosylase, hOGG1}, author = {Crenshaw, Charisse M. and Nam, Kwangho and Oo, Kimberly and Kutchukian, Peter S. and Bowman, Brian R. and Karplus, Martin and Verdine, Gregory L.}, doi = {10.1074/jbc.M111.316497}, issn = {0021-9258}, year = {2012}, date = {2012-07-01}, journal = {JOURNAL OF BIOLOGICAL CHEMISTRY}, volume = {287}, number = {30}, pages = {24916--24928}, abstract = {A poorly understood aspect of DNA repair proteins is their ability to identify exceedingly rare sites of damage embedded in a large excess of nearly identical undamaged DNA, while catalyzing repair only at the damaged sites. Progress toward understanding this problem has been made by comparing the structures and biochemical behavior of these enzymes when they are presented with either a target lesion or a corresponding undamaged nucleobase. Trapping and analyzing such DNA-protein complexes is particularly difficult in the case of base extrusion DNA repair proteins because of the complexity of the repair reaction, which involves extrusion of the target base from DNA followed by its insertion into the active site where glycosidic bond cleavage is catalyzed. Here we report the structure of a human 8-oxoguanine (oxoG) DNA glycosylase, hOGG1, in which a normal guanine from DNA has been forcibly inserted into the enzyme active site. Although the interactions of the nucleobase with the active site are only subtly different for G versus oxoG, hOGG1 fails to catalyze excision of the normal nucleobase. This study demonstrates that even if hOGG1 mistakenly inserts a normal base into its active site, the enzyme can still reject it on the basis of catalytic incompatibility.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A poorly understood aspect of DNA repair proteins is their ability to identify exceedingly rare sites of damage embedded in a large excess of nearly identical undamaged DNA, while catalyzing repair only at the damaged sites. Progress toward understanding this problem has been made by comparing the structures and biochemical behavior of these enzymes when they are presented with either a target lesion or a corresponding undamaged nucleobase. Trapping and analyzing such DNA-protein complexes is particularly difficult in the case of base extrusion DNA repair proteins because of the complexity of the repair reaction, which involves extrusion of the target base from DNA followed by its insertion into the active site where glycosidic bond cleavage is catalyzed. Here we report the structure of a human 8-oxoguanine (oxoG) DNA glycosylase, hOGG1, in which a normal guanine from DNA has been forcibly inserted into the enzyme active site. Although the interactions of the nucleobase with the active site are only subtly different for G versus oxoG, hOGG1 fails to catalyze excision of the normal nucleobase. This study demonstrates that even if hOGG1 mistakenly inserts a normal base into its active site, the enzyme can still reject it on the basis of catalytic incompatibility. |
Karthikeyan, Ganesan ; Zambaldo, Claudio ; Barluenga, Sofia ; Zoete, Vincent ; Karplus, Martin ; Winssinger, Nicolas Asymmetric Synthesis of Pochonin E and F, Revision of Their Proposed Structure, and Their Conversion to Potent Hsp90 Inhibitors Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 18 (29), pp. 8978–8986, 2012, ISSN: 0947-6539. @article{karthikeyan_asymmetric_2012, title = {Asymmetric Synthesis of Pochonin E and F, Revision of Their Proposed Structure, and Their Conversion to Potent Hsp90 Inhibitors}, author = {Karthikeyan, Ganesan and Zambaldo, Claudio and Barluenga, Sofia and Zoete, Vincent and Karplus, Martin and Winssinger, Nicolas}, doi = {10.1002/chem.201200546}, issn = {0947-6539}, year = {2012}, date = {2012-07-01}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {18}, number = {29}, pages = {8978--8986}, abstract = {A concise and modular synthesis of pochonin E and F, and their epimers at C-6 established the correct stereochemistry of these two natural products. Several members of the pochonin family have been shown to bind the heat shock protein 90 (Hsp90), which has been the focus of intense drug discovery efforts. Pochonin E and F as well as their epimers were derivatized into the corresponding pochoximes and further modified at the C-6 position. Molecular dynamics simulations, docking studies, and Hsp90 affinity measurements were performed to evaluate the impact of these modifications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A concise and modular synthesis of pochonin E and F, and their epimers at C-6 established the correct stereochemistry of these two natural products. Several members of the pochonin family have been shown to bind the heat shock protein 90 (Hsp90), which has been the focus of intense drug discovery efforts. Pochonin E and F as well as their epimers were derivatized into the corresponding pochoximes and further modified at the C-6 position. Molecular dynamics simulations, docking studies, and Hsp90 affinity measurements were performed to evaluate the impact of these modifications. |
Roche, Cecile ; Sour, Angelique ; Sauvage, Jean-Pierre A Flexible Copper(I)-Complexed [4]Rotaxane Containing Two Face-to-Face Porphyrinic Plates that Behaves as a Distensible Receptor Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 18 (27), pp. 8366–8376, 2012, ISSN: 0947-6539. @article{roche_flexible_2012, title = {A Flexible Copper(I)-Complexed [4]Rotaxane Containing Two Face-to-Face Porphyrinic Plates that Behaves as a Distensible Receptor}, author = {Roche, Cecile and Sour, Angelique and Sauvage, Jean-Pierre}, doi = {10.1002/chem.201200389}, issn = {0947-6539}, year = {2012}, date = {2012-07-01}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {18}, number = {27}, pages = {8366--8376}, abstract = {A new cyclic [4]rotaxane composed of two flexible bis-macrocycles and two rigid axles is described. Each bis-macrocycle consists of two rings attached to antipodal meso positions of a central Zn porphyrin through single C?C bonds. Each ring incorporates a 2,9-diphenyl-1,10-phenanthroline chelation site. The axles contain two coplanar bidentate sites derived from the 2,2'-bipyridine motif. The building blocks were assembled by using a one-pot threading-and-stoppering reaction, which afforded the [4]rotaxane in 50?% yield. The gathering-and-threading effect of copper(I) was utilised in the formation of a [4]pseudorotaxane, which was immediately converted to the corresponding [4]rotaxane by a quadruple CuAAC stoppering reaction. The rotaxane contains two face-to-face zinc porphyrins, which allowed the coordination of ditopic guest substrates. The rotaxane host showed remarkable flexibility and was able to adjust its conformation to the guest size. It can be distended and accommodate rod-like guests of 2.6 to 15.8 angstrom in length.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A new cyclic [4]rotaxane composed of two flexible bis-macrocycles and two rigid axles is described. Each bis-macrocycle consists of two rings attached to antipodal meso positions of a central Zn porphyrin through single C?C bonds. Each ring incorporates a 2,9-diphenyl-1,10-phenanthroline chelation site. The axles contain two coplanar bidentate sites derived from the 2,2'-bipyridine motif. The building blocks were assembled by using a one-pot threading-and-stoppering reaction, which afforded the [4]rotaxane in 50?% yield. The gathering-and-threading effect of copper(I) was utilised in the formation of a [4]pseudorotaxane, which was immediately converted to the corresponding [4]rotaxane by a quadruple CuAAC stoppering reaction. The rotaxane contains two face-to-face zinc porphyrins, which allowed the coordination of ditopic guest substrates. The rotaxane host showed remarkable flexibility and was able to adjust its conformation to the guest size. It can be distended and accommodate rod-like guests of 2.6 to 15.8 angstrom in length. |
Benhamou, P -Y; Catargi, B; Delenne, B; Guerci, B; Hanaire, H; Jeandidier, N; Leroy, R; Meyer, L; Penfomis, A; Radermecker, R -P; Renard, E; Baillot-Rudoni, S; Riveline, J -P; Schaepelynck, P; Sola-Gazagnes, A; Sulmont, V; Tubiana-Rufi, N; Durain, D; Mantovani, I; SFD, ; SFE, ; Impl, EVADIAC Grp EVAluation Diabet Real-time continuous glucose monitoring (CGM) integrated into the treatment of type 1 diabetes: Consensus of experts from SFD, EVADIAC and SFE Journal Article In: DIABETES & METABOLISM, 38 (4), pp. S67–S83, 2012, ISSN: 1262-3636. @article{benhamou_real-time_2012, title = {Real-time continuous glucose monitoring (CGM) integrated into the treatment of type 1 diabetes: Consensus of experts from SFD, EVADIAC and SFE}, author = {Benhamou, P. -Y. and Catargi, B. and Delenne, B. and Guerci, B. and Hanaire, H. and Jeandidier, N. and Leroy, R. and Meyer, L. and Penfomis, A. and Radermecker, R. -P and Renard, E. and Baillot-Rudoni, S. and Riveline, J. -P and Schaepelynck, P. and Sola-Gazagnes, A. and Sulmont, V. and Tubiana-Rufi, N. and Durain, D. and Mantovani, I. and {SFD} and {SFE} and Impl, EVADIAC Grp EVAluation Diabet}, doi = {10.1016/S1262-3636(12)71538-0}, issn = {1262-3636}, year = {2012}, date = {2012-07-01}, journal = {DIABETES & METABOLISM}, volume = {38}, number = {4}, pages = {S67--S83}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
El Debs, Bachir ; Utharala, Ramesh ; Balyasnikova, Irina V; Griffiths, Andrew D; Merten, Christoph A Functional single-cell hybridoma screening using droplet-based microfluidics Journal Article In: Proceedings of the National Academy of Sciences of the United States of America, 109 (29), pp. 11570–11575, 2012, ISSN: 1091-6490. @article{el_debs_functional_2012, title = {Functional single-cell hybridoma screening using droplet-based microfluidics}, author = {El Debs, Bachir and Utharala, Ramesh and Balyasnikova, Irina V. and Griffiths, Andrew D. and Merten, Christoph A.}, doi = {10.1073/pnas.1204514109}, issn = {1091-6490}, year = {2012}, date = {2012-07-01}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {109}, number = {29}, pages = {11570--11575}, abstract = {Monoclonal antibodies can specifically bind or even inhibit drug targets and have hence become the fastest growing class of human therapeutics. Although they can be screened for binding affinities at very high throughput using systems such as phage display, screening for functional properties (e.g., the inhibition of a drug target) is much more challenging. Typically these screens require the generation of immortalized hybridoma cells, as well as clonal expansion in microtiter plates over several weeks, and the number of clones that can be assayed is typically no more than a few thousand. We present here a microfluidic platform allowing the functional screening of up to 300,000 individual hybridoma cell clones within less than a day. This approach should also be applicable to nonimmortalized primary B-cells, as no cell proliferation is required: Individual cells are encapsulated into aqueous microdroplets and assayed directly for the release of antibodies inhibiting a drug target based on fluorescence. We used this system to perform a model screen for antibodies that inhibit angiotensin converting enzyme 1, a target for hypertension and congestive heart failure drugs. When cells expressing these antibodies were spiked into an unrelated hybridoma cell population in a ratio of 1:10,000 we observed a 9,400-fold enrichment after fluorescence activated droplet sorting. A wide variance in antibody expression levels at the single-cell level within a single hybridoma line was observed and high expressors could be successfully sorted and recultivated.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Monoclonal antibodies can specifically bind or even inhibit drug targets and have hence become the fastest growing class of human therapeutics. Although they can be screened for binding affinities at very high throughput using systems such as phage display, screening for functional properties (e.g., the inhibition of a drug target) is much more challenging. Typically these screens require the generation of immortalized hybridoma cells, as well as clonal expansion in microtiter plates over several weeks, and the number of clones that can be assayed is typically no more than a few thousand. We present here a microfluidic platform allowing the functional screening of up to 300,000 individual hybridoma cell clones within less than a day. This approach should also be applicable to nonimmortalized primary B-cells, as no cell proliferation is required: Individual cells are encapsulated into aqueous microdroplets and assayed directly for the release of antibodies inhibiting a drug target based on fluorescence. We used this system to perform a model screen for antibodies that inhibit angiotensin converting enzyme 1, a target for hypertension and congestive heart failure drugs. When cells expressing these antibodies were spiked into an unrelated hybridoma cell population in a ratio of 1:10,000 we observed a 9,400-fold enrichment after fluorescence activated droplet sorting. A wide variance in antibody expression levels at the single-cell level within a single hybridoma line was observed and high expressors could be successfully sorted and recultivated. |
Aouani, Heykel ; Hostein, Richard ; Mahboub, Oussama ; Devaux, Eloise ; Rigneault, Herve ; Ebbesen, Thomas W; Wenger, Jerome Saturated excitation of fluorescence to quantify excitation enhancement in aperture antennas Journal Article In: OPTICS EXPRESS, 20 (16), pp. 18085–18090, 2012, ISSN: 1094-4087. @article{aouani_saturated_2012, title = {Saturated excitation of fluorescence to quantify excitation enhancement in aperture antennas}, author = {Aouani, Heykel and Hostein, Richard and Mahboub, Oussama and Devaux, Eloise and Rigneault, Herve and Ebbesen, Thomas W. and Wenger, Jerome}, doi = {10.1364/OE.20.018085}, issn = {1094-4087}, year = {2012}, date = {2012-07-01}, journal = {OPTICS EXPRESS}, volume = {20}, number = {16}, pages = {18085--18090}, abstract = {Fluorescence spectroscopy is widely used to probe the electromagnetic intensity amplification on optical antennas, yet measuring the excitation intensity amplification is a challenge, as the detected fluorescence signal is an intricate combination of excitation and emission. Here, we describe a novel approach to quantify the electromagnetic amplification in aperture antennas by taking advantage of the intrinsic non linear properties of the fluorescence process. Experimental measurements of the fundamental f and second harmonic 2f amplitudes of the fluorescence signal upon excitation modulation are used to quantify the electromagnetic intensity amplification with plasmonic aperture antennas. (C) 2012 Optical Society of America}, keywords = {}, pubstate = {published}, tppubtype = {article} } Fluorescence spectroscopy is widely used to probe the electromagnetic intensity amplification on optical antennas, yet measuring the excitation intensity amplification is a challenge, as the detected fluorescence signal is an intricate combination of excitation and emission. Here, we describe a novel approach to quantify the electromagnetic amplification in aperture antennas by taking advantage of the intrinsic non linear properties of the fluorescence process. Experimental measurements of the fundamental f and second harmonic 2f amplitudes of the fluorescence signal upon excitation modulation are used to quantify the electromagnetic intensity amplification with plasmonic aperture antennas. (C) 2012 Optical Society of America |
Yi, J-M; Cuche, A; de Leon-Perez, F; Degiron, A; Laux, E; Devaux, E; Genet, C; Alegret, J; Martin-Moreno, L; Ebbesen, T W Diffraction Regimes of Single Holes Journal Article In: PHYSICAL REVIEW LETTERS, 109 (2), 2012, ISSN: 0031-9007. @article{yi_diffraction_2012, title = {Diffraction Regimes of Single Holes}, author = {Yi, J-M. and Cuche, A. and de Leon-Perez, F. and Degiron, A. and Laux, E. and Devaux, E. and Genet, C. and Alegret, J. and Martin-Moreno, L. and Ebbesen, T. W.}, doi = {10.1103/PhysRevLett.109.023901}, issn = {0031-9007}, year = {2012}, date = {2012-07-01}, journal = {PHYSICAL REVIEW LETTERS}, volume = {109}, number = {2}, abstract = {We investigate both experimentally and theoretically the far-field diffraction patterns of single circular apertures as a function of their diameters d and at a given illumination wavelength lambda. We observe the transition between the well-known pseudoscalar regime of large holes (d textbackslashtextbackslashtextgreatertextbackslashtextbackslashtextgreater lambda) and the less-known vectorial regime of subwavelength ones (d textbackslashtextbackslashtextlesstextbackslashtextbackslashtextless lambda). Four different diffraction regimes are identified for different d/lambda regions, each one with its polarization dependence. A thorough comparison with a theoretical model, which takes into account both finite hole size and the dielectric properties of the metal, allows us to explain and understand the physical processes leading to this behavior. Our results reveal the subtle interplay between two competing factors, one related to polarization symmetries associated with surface-plasmon excitations and the other originating in the coupling of the field to the waveguide mode of the aperture.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We investigate both experimentally and theoretically the far-field diffraction patterns of single circular apertures as a function of their diameters d and at a given illumination wavelength lambda. We observe the transition between the well-known pseudoscalar regime of large holes (d textbackslashtextbackslashtextgreatertextbackslashtextbackslashtextgreater lambda) and the less-known vectorial regime of subwavelength ones (d textbackslashtextbackslashtextlesstextbackslashtextbackslashtextless lambda). Four different diffraction regimes are identified for different d/lambda regions, each one with its polarization dependence. A thorough comparison with a theoretical model, which takes into account both finite hole size and the dielectric properties of the metal, allows us to explain and understand the physical processes leading to this behavior. Our results reveal the subtle interplay between two competing factors, one related to polarization symmetries associated with surface-plasmon excitations and the other originating in the coupling of the field to the waveguide mode of the aperture. |
Gorodetski, Y; Bliokh, K Y; Stein, B; Genet, C; Shitrit, N; Kleiner, V; Hasman, E; Ebbesen, T W Weak Measurements of Light Chirality with a Plasmonic Slit Journal Article In: PHYSICAL REVIEW LETTERS, 109 (1), 2012, ISSN: 0031-9007. @article{gorodetski_weak_2012, title = {Weak Measurements of Light Chirality with a Plasmonic Slit}, author = {Gorodetski, Y. and Bliokh, K. Y. and Stein, B. and Genet, C. and Shitrit, N. and Kleiner, V. and Hasman, E. and Ebbesen, T. W.}, doi = {10.1103/PhysRevLett.109.013901}, issn = {0031-9007}, year = {2012}, date = {2012-07-01}, journal = {PHYSICAL REVIEW LETTERS}, volume = {109}, number = {1}, abstract = {We examine, both experimentally and theoretically, an interaction of tightly focused polarized light with a slit on a metal surface supporting plasmon-polariton modes. Remarkably, this simple system can be highly sensitive to the polarization of the incident light and offers a perfect quantum weak measurement tool with a built-in postselection in the plasmon-polariton mode. We observe the plasmonic spin Hall effect in both coordinate and momentum spaces which is interpreted as weak measurements of the helicity of light with real and imaginary weak values determined by the input polarization. Our experiment combines the advantages of (i) quantum weak measurements, (ii) near-field plasmonic systems, and (iii) high-numerical aperture microscopy in employing the spin-orbit interaction of light and probing light chirality.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We examine, both experimentally and theoretically, an interaction of tightly focused polarized light with a slit on a metal surface supporting plasmon-polariton modes. Remarkably, this simple system can be highly sensitive to the polarization of the incident light and offers a perfect quantum weak measurement tool with a built-in postselection in the plasmon-polariton mode. We observe the plasmonic spin Hall effect in both coordinate and momentum spaces which is interpreted as weak measurements of the helicity of light with real and imaginary weak values determined by the input polarization. Our experiment combines the advantages of (i) quantum weak measurements, (ii) near-field plasmonic systems, and (iii) high-numerical aperture microscopy in employing the spin-orbit interaction of light and probing light chirality. |
Zalewski, Leszek ; Mativetsky, Jeffrey M; Brovelli, Sergio ; Bonini, Massimo ; Crivillers, Nuria ; Breiner, Thomas ; Anderson, Harry L; Cacialli, Franco ; Samori, Paolo A Quaterthiophene-Based Rotaxane: Synthesis, Spectroscopy, and Self-Assembly at Surfaces Journal Article In: SMALL, 8 (12), pp. 1835–1839, 2012, ISSN: 1613-6810. @article{zalewski_quaterthiophene-based_2012, title = {A Quaterthiophene-Based Rotaxane: Synthesis, Spectroscopy, and Self-Assembly at Surfaces}, author = {Zalewski, Leszek and Mativetsky, Jeffrey M. and Brovelli, Sergio and Bonini, Massimo and Crivillers, Nuria and Breiner, Thomas and Anderson, Harry L. and Cacialli, Franco and Samori, Paolo}, doi = {10.1002/smll.201102281}, issn = {1613-6810}, year = {2012}, date = {2012-06-01}, journal = {SMALL}, volume = {8}, number = {12}, pages = {1835--1839}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Kovaricek, Petr ; Lehn, Jean-Marie Merging Constitutional and Motional Covalent Dynamics in Reversible Imine Formation and Exchange Processes Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 134 (22), pp. 9446–9455, 2012, ISSN: 0002-7863. @article{kovaricek_merging_2012, title = {Merging Constitutional and Motional Covalent Dynamics in Reversible Imine Formation and Exchange Processes}, author = {Kovaricek, Petr and Lehn, Jean-Marie}, doi = {10.1021/ja302793c}, issn = {0002-7863}, year = {2012}, date = {2012-06-01}, journal = {JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, volume = {134}, number = {22}, pages = {9446--9455}, abstract = {The formation and exchange processes of imines of benzaldehyde have been studied, showing that the former has features of for dynamic covalent chemistry, displaying high efficiency and fast rates. The monoimines formed with aliphatic a,alpha,omega-diamines display an internal exchange process of self-transimination type, inducing a local motion of either “stepping-in-place” or “single-step” type by bond interchange, whose rate decreases rapidly with the distance of the terminal amino groups. Control of the speed of the process over a wide range may be achieved by substituents, solvent composition, and temperature. These monoimines also undergo intermolecular exchange, thus merging motional and constitutional covalent behavior within the same molecule. With polyamines, the monoimines formed execute internal motions that have been characterized by extensive one-dimensional, two-dimensional, and EXSY proton NMR studies. In particular, with linear polyamines, nondirectional displacement occurs by shifting of the aldehyde residue along the polyamine chain serving as molecular track. lmines thus behave as simple prototypes of systems displaying relative motions of molecular moieties, a subject of high current interest in the investigation of synthetic and biological molecular motors. The motional processes described are of dynamic covalent nature and take place without change in molecular constitution. They thus represent a category of dynamic covalent motions, resulting from reversible covalent bond formation and dissociation. They extend dynamic covalent chemistry into the area of molecular motions. A major further step will be to achieve control of directionality. The results reported here for imines open wide perspectives, together with other chemical groups, for the implementation of such features in multifunctional molecules toward the design of molecular devices presenting a complex combination of motional and constitutional dynamic behaviors.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The formation and exchange processes of imines of benzaldehyde have been studied, showing that the former has features of for dynamic covalent chemistry, displaying high efficiency and fast rates. The monoimines formed with aliphatic a,alpha,omega-diamines display an internal exchange process of self-transimination type, inducing a local motion of either “stepping-in-place” or “single-step” type by bond interchange, whose rate decreases rapidly with the distance of the terminal amino groups. Control of the speed of the process over a wide range may be achieved by substituents, solvent composition, and temperature. These monoimines also undergo intermolecular exchange, thus merging motional and constitutional covalent behavior within the same molecule. With polyamines, the monoimines formed execute internal motions that have been characterized by extensive one-dimensional, two-dimensional, and EXSY proton NMR studies. In particular, with linear polyamines, nondirectional displacement occurs by shifting of the aldehyde residue along the polyamine chain serving as molecular track. lmines thus behave as simple prototypes of systems displaying relative motions of molecular moieties, a subject of high current interest in the investigation of synthetic and biological molecular motors. The motional processes described are of dynamic covalent nature and take place without change in molecular constitution. They thus represent a category of dynamic covalent motions, resulting from reversible covalent bond formation and dissociation. They extend dynamic covalent chemistry into the area of molecular motions. A major further step will be to achieve control of directionality. The results reported here for imines open wide perspectives, together with other chemical groups, for the implementation of such features in multifunctional molecules toward the design of molecular devices presenting a complex combination of motional and constitutional dynamic behaviors. |
Schlegel, A; Lehn, J M; Humar, B; Graf, R; Dutkowski, P; Clavien, P A Myo-Inositol trispyrophosphate improves viability of liver grafts donated after cardiac death Journal Article In: BRITISH JOURNAL OF SURGERY, 99 (5), pp. 17, 2012, ISSN: 0007-1323. @article{schlegel_myo-inositol_2012, title = {Myo-Inositol trispyrophosphate improves viability of liver grafts donated after cardiac death}, author = {Schlegel, A. and Lehn, J. M. and Humar, B. and Graf, R. and Dutkowski, P. and Clavien, P. A.}, issn = {0007-1323}, year = {2012}, date = {2012-06-01}, journal = {BRITISH JOURNAL OF SURGERY}, volume = {99}, number = {5}, pages = {17}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Henkel, N; Cinti, F; Jain, P; Pupillo, G; Pohl, T Supersolid Vortex Crystals in Rydberg-Dressed Bose-Einstein Condensates Journal Article In: PHYSICAL REVIEW LETTERS, 108 (26), 2012, ISSN: 0031-9007. @article{henkel_supersolid_2012, title = {Supersolid Vortex Crystals in Rydberg-Dressed Bose-Einstein Condensates}, author = {Henkel, N. and Cinti, F. and Jain, P. and Pupillo, G. and Pohl, T.}, doi = {10.1103/PhysRevLett.108.265301}, issn = {0031-9007}, year = {2012}, date = {2012-06-01}, journal = {PHYSICAL REVIEW LETTERS}, volume = {108}, number = {26}, abstract = {We study rotating quasi-two-dimensional Bose-Einstein condensates, in which atoms are dressed to a highly excited Rydberg state. This leads to weak effective interactions that induce a transition to a mesoscopic supersolid state. Considering slow rotation, we determine its superfluidity using quantum Monte Carlo simulations as well as mean field calculations. For rapid rotation, the latter reveal an interesting competition between the supersolid crystal structure and the rotation-induced vortex lattice that gives rise to new phases, including arrays of mesoscopic vortex crystals.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We study rotating quasi-two-dimensional Bose-Einstein condensates, in which atoms are dressed to a highly excited Rydberg state. This leads to weak effective interactions that induce a transition to a mesoscopic supersolid state. Considering slow rotation, we determine its superfluidity using quantum Monte Carlo simulations as well as mean field calculations. For rapid rotation, the latter reveal an interesting competition between the supersolid crystal structure and the rotation-induced vortex lattice that gives rise to new phases, including arrays of mesoscopic vortex crystals. |
Publications
2013 |
Large Work Function Shift of Gold Induced by a Novel Perfluorinated Azobenzene-Based Self-Assembled Monolayer Journal Article In: ADVANCED MATERIALS, 25 (3, SI), pp. 432–436, 2013, ISSN: 0935-9648. |
Controlling the morphology of conductive PEDOT by in situ electropolymerization: from thin films to nanowires with variable electrical properties Journal Article In: NANOSCALE, 5 (17), pp. 7756–7761, 2013, ISSN: 2040-3364. |
Supramolecular Ħ-bonded porous networks at surfaces: exploiting primary and secondary interactions in a bi-component melamine-xanthine system Journal Article In: PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 15 (30), pp. 12442–12446, 2013, ISSN: 1463-9076. |
Nanoscale insight into the exfoliation mechanism of graphene with organic dyes: effect of charge, dipole and molecular structure Journal Article In: NANOSCALE, 5 (10), pp. 4205–4216, 2013, ISSN: 2040-3364. |
Orthogonal self-assembly and selective solvent vapour annealing: simplified processing of a photovoltaic blend Journal Article In: CHEMICAL COMMUNICATIONS, 49 (39), pp. 4322–4324, 2013, ISSN: 1359-7345. |
A Simplified Confinement Method for Calculating Absolute Free Energies and Free Energy and Entropy Differences Journal Article In: JOURNAL OF PHYSICAL CHEMISTRY B, 117 (3), pp. 750–762, 2013, ISSN: 1520-6106. |
Tuning the planarity of [2 x 2] grids Journal Article In: CRYSTENGCOMM, 15 (44), pp. 9128–9134, 2013, ISSN: 1466-8033. |
Grid-double-helicate interconversion Journal Article In: CHEMICAL COMMUNICATIONS, 49 (51), pp. 5733–5735, 2013, ISSN: 1359-7345. |
Generation of supramolecular microcapsules by oxidative covalent polymerization of a ditopic supramolecular building block Journal Article In: POLYMER CHEMISTRY, 4 (10), pp. 2949–2957, 2013, ISSN: 1759-9954. |
Photo- and Thermoresponsive Supramolecular Assemblies: Reversible Photorelease of K plus Ions and Constitutional Dynamics Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 52 (14), pp. 3940–3943, 2013, ISSN: 1433-7851. |
Motility efficiency and spatiotemporal synchronization in non-metastatic vs. metastatic breast cancer cells Journal Article In: INTEGRATIVE BIOLOGY, 5 (12), pp. 1464–1473, 2013, ISSN: 1757-9694. |
Quantum phases of dipolar bosons in bilayer geometry Journal Article In: NEW JOURNAL OF PHYSICS, 15 , 2013, ISSN: 1367-2630. |
Synthesis of a metal-free coordinating ring via formation of a cleavable [2]catenane Journal Article In: CHEMICAL COMMUNICATIONS, 49 (92), pp. 10790–10792, 2013, ISSN: 1359-7345. |
Dynamic topomerization of Cu(I)-complexed pseudorotaxanes Journal Article In: CHEMICAL COMMUNICATIONS, 49 (13), pp. 1261–1263, 2013, ISSN: 1359-7345. |
Topologically complex molecules obtained by transition metal templation: it is the presentation that determines the synthesis strategy Journal Article In: NEW JOURNAL OF CHEMISTRY, 37 (1), pp. 49–57, 2013, ISSN: 1144-0546. |
Base-etch removal of a ligand shell in thin films of ZnO nanoparticles for electronic applications Journal Article In: JOURNAL OF MATERIALS CHEMISTRY C, 1 (42), pp. 7111–7116, 2013, ISSN: 2050-7526. |
Functionalized ZnO nanoparticles for thin-film transistors: support of ligand removal by non-thermal methods Journal Article In: JOURNAL OF MATERIALS CHEMISTRY C, 1 (18), pp. 3098–3103, 2013, ISSN: 2050-7526. |
Toxoplasma gondii secretory proteins bind to sulfated heparin structures Journal Article In: GLYCOBIOLOGY, 23 (1), pp. 106–120, 2013, ISSN: 0959-6658. |
Polariton Dynamics under Strong Light-Molecule Coupling Journal Article In: CHEMPHYSCHEM, 14 (1), pp. 125–131, 2013, ISSN: 1439-4235. |
2012 |
Organocatalysis of C=N/C=N and C=C/C=N Exchange in Dynamic Covalent Chemistry Journal Article In: HELVETICA CHIMICA ACTA, 95 (12), pp. 2635–2651, 2012, ISSN: 0018-019X. |
Synthesis and Copper(I)-Driven Disaggregation of a Zinc-Complexed Phthalocyanine Bearing Four Lateral Coordinating Rings Journal Article In: EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, (35), pp. 6888–6894, 2012, ISSN: 1434-193X. |
Separation of distinct adhesion complexes and associated cytoskeleton by a micro-stencil-printing method Journal Article In: CELL ADHESION & MIGRATION, 6 (6), pp. 471–475, 2012, ISSN: 1933-6918. |
Ultrasensitive detection of toxic cations through changes in the tunnelling current across films of striped nanoparticles Journal Article In: NATURE MATERIALS, 11 (11), pp. 978–985, 2012, ISSN: 1476-1122. |
Encapsulation of Luminescent Homoleptic [Ru(dpp)3]2+-Type Chromophores within an Amphiphilic Dendritic Environment Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 18 (48), pp. 15424–15432, 2012, ISSN: 0947-6539. |
A perfect plasmonic quarter-wave plate Journal Article In: APPLIED PHYSICS LETTERS, 101 (20), 2012, ISSN: 0003-6951. |
Increased efficiency of light-emitting diodes incorporating anodes functionalized with fluorinated azobenzene monolayers and a green-emitting polyfluorene derivative Journal Article In: APPLIED PHYSICS LETTERS, 101 (15), 2012, ISSN: 0003-6951. |
Trans-endothelial passage of chemical vectors in a skeletal muscle endothelium model: Effect of inflammatory cytokines. Journal Article In: HUMAN GENE THERAPY, 23 (10), pp. A140, 2012, ISSN: 1043-0342. |
Driven-dissipative dynamics of a strongly interacting Rydberg gas Journal Article In: PHYSICAL REVIEW A, 86 (4), 2012, ISSN: 1050-2947. |
Condensed Matter Theory of Dipolar Quantum Gases Journal Article In: CHEMICAL REVIEWS, 112 (9, SI), pp. 5012–5061, 2012, ISSN: 0009-2665. |
Preparation of Copper(I) Pseudo-rotaxanes from Bis-phosphine Ligands Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 18 (39), pp. 12192–12195, 2012, ISSN: 0947-6539. |
Sensitisation of the Near-Infrared Emission of NdIII from the Singlet State of Porphyrins Bearing Four 8-Hydroxyquinolinylamide Chelates Journal Article In: CHEMPHYSCHEM, 13 (13), pp. 3163–3171, 2012, ISSN: 1439-4235. |
Multiscale Charge Injection and Transport Properties in Self-Assembled Monolayers of Biphenyl Thiols with Varying Torsion Angles Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 18 (33), pp. 10335–10347, 2012, ISSN: 0947-6539. |
Optically switchable transistor via energy-level phototuning in a bicomponent organic semiconductor Journal Article In: NATURE CHEMISTRY, 4 (8), pp. 675–679, 2012, ISSN: 1755-4330. |
Adaptation of Dynamic Covalent Systems of Imine Constituents to Medium Change by Component Redistribution under Reversible Phase Separation Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 134 (30), pp. 12861–12868, 2012, ISSN: 0002-7863. |
Stereochemistry of Molecular Figures-of-Eight Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 18 (33), pp. 10312–10323, 2012, ISSN: 0947-6539. |
Brownian Motion in a Designer Force Field: Dynamical Effects of Negative Refraction on Nanoparticles Journal Article In: NANO LETTERS, 12 (8), pp. 4329–4332, 2012, ISSN: 1530-6984. |
Optically switchable organic field-effect transistors based on photoresponsive gold nanoparticles blended with poly(3-hexylthiophene) Journal Article In: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 109 (31), pp. 12375–12380, 2012, ISSN: 0027-8424. |
Analysis and Elimination of a Bias in Targeted Molecular Dynamics Simulations of Conformational Transitions: Application to Calmodulin Journal Article In: JOURNAL OF PHYSICAL CHEMISTRY B, 116 (29, SI), pp. 8584–8603, 2012, ISSN: 1520-6106. |
Enforced Presentation of an Extrahelical Guanine to the Lesion Recognition Pocket of Human 8-Oxoguanine Glycosylase, hOGG1 Journal Article In: JOURNAL OF BIOLOGICAL CHEMISTRY, 287 (30), pp. 24916–24928, 2012, ISSN: 0021-9258. |
Asymmetric Synthesis of Pochonin E and F, Revision of Their Proposed Structure, and Their Conversion to Potent Hsp90 Inhibitors Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 18 (29), pp. 8978–8986, 2012, ISSN: 0947-6539. |
A Flexible Copper(I)-Complexed [4]Rotaxane Containing Two Face-to-Face Porphyrinic Plates that Behaves as a Distensible Receptor Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 18 (27), pp. 8366–8376, 2012, ISSN: 0947-6539. |
Real-time continuous glucose monitoring (CGM) integrated into the treatment of type 1 diabetes: Consensus of experts from SFD, EVADIAC and SFE Journal Article In: DIABETES & METABOLISM, 38 (4), pp. S67–S83, 2012, ISSN: 1262-3636. |
Functional single-cell hybridoma screening using droplet-based microfluidics Journal Article In: Proceedings of the National Academy of Sciences of the United States of America, 109 (29), pp. 11570–11575, 2012, ISSN: 1091-6490. |
Saturated excitation of fluorescence to quantify excitation enhancement in aperture antennas Journal Article In: OPTICS EXPRESS, 20 (16), pp. 18085–18090, 2012, ISSN: 1094-4087. |
Diffraction Regimes of Single Holes Journal Article In: PHYSICAL REVIEW LETTERS, 109 (2), 2012, ISSN: 0031-9007. |
Weak Measurements of Light Chirality with a Plasmonic Slit Journal Article In: PHYSICAL REVIEW LETTERS, 109 (1), 2012, ISSN: 0031-9007. |
A Quaterthiophene-Based Rotaxane: Synthesis, Spectroscopy, and Self-Assembly at Surfaces Journal Article In: SMALL, 8 (12), pp. 1835–1839, 2012, ISSN: 1613-6810. |
Merging Constitutional and Motional Covalent Dynamics in Reversible Imine Formation and Exchange Processes Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 134 (22), pp. 9446–9455, 2012, ISSN: 0002-7863. |
Myo-Inositol trispyrophosphate improves viability of liver grafts donated after cardiac death Journal Article In: BRITISH JOURNAL OF SURGERY, 99 (5), pp. 17, 2012, ISSN: 0007-1323. |
Supersolid Vortex Crystals in Rydberg-Dressed Bose-Einstein Condensates Journal Article In: PHYSICAL REVIEW LETTERS, 108 (26), 2012, ISSN: 0031-9007. |