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Yang Yu Theodore Tyrikos‐Ergas Yuntao Zhu Giulio Fittolani Vittorio Bordoni Ankush Singhal Richard J. Fair Andrea Grafmüller Peter H. Seeberger Martina Delbianco 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(37):13261-13266
A dense hydrogen‐bond network is responsible for the mechanical and structural properties of polysaccharides. Random derivatization alters the properties of the bulk material by disrupting the hydrogen bonds, but obstructs detailed structure–function correlations. We have prepared well‐defined unnatural oligosaccharides including methylated, deoxygenated, deoxyfluorinated, as well as carboxymethylated cellulose and chitin analogues with full control over the degree and pattern of substitution. Molecular dynamics simulations and crystallographic analysis show how distinct hydrogen‐bond modifications drastically affect the solubility, aggregation behavior, and crystallinity of carbohydrate materials. This systematic approach to establishing detailed structure–property correlations will guide the synthesis of novel, tailor‐made carbohydrate materials. 相似文献
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Dr. Franck Bertorelle Dr. K. David Wegner Martina Perić Bakulić Hussein Fakhouri Clothilde Comby-Zerbino Dr. Amin Sagar Dr. Pau Bernadó Dr. Ute Resch-Genger Prof. Vlasta Bonačić-Koutecký Dr. Xavier Le Guével Dr. Rodolphe Antoine 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(39):e202200570
Atomically precise gold nanoclusters are a fascinating class of nanomaterials that exhibit molecule-like properties and have outstanding photoluminescence (PL). Their ultrasmall size, molecular chemistry, and biocompatibility make them extremely appealing for selective biomolecule labeling in investigations of biological mechanisms at the cellular and anatomical levels. In this work, we report a simple route to incorporate a preformed Au25 nanocluster into a model bovine serum albumin (BSA) protein. A new approach combining small-angle X-ray scattering and molecular modeling provides a clear localization of a single Au25 within the protein to a cysteine residue on the gold nanocluster surface. Attaching Au25 to BSA strikingly modifies the PL properties with enhancement and a redshift in the second near-infrared (NIR-II) window. This study paves the way to conrol the design of selective sensitive probes in biomolecules through a ligand-based strategy to enable the optical detection of biomolecules in a cellular environment by live imaging. 相似文献
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Alvis Mengots Andreas Erbs Hillers-Bendtsen Dr. Sandra Doria Frederik Ørsted Kjeldal Nicolai Machholdt Høyer Dr. Anne Ugleholdt Petersen Prof. Dr. Kurt V. Mikkelsen Dr. Mariangela Di Donato Prof. Dr. Martina Cacciarini Prof. Dr. Mogens Brøndsted Nielsen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(48):12437-12446
Photoswitch triads comprising two dihydroazulene (DHA) units in conjugation with a central trans-azobenzene (AZB) unit were prepared in stepwise protocols starting from meta- and para-disubstituted azobenzenes. The para-connected triad had significantly altered optical properties and lacked the photoactivity of the separate photochromes. In contrast, for the meta-connected triad, all three photochromes could be photoisomerized to generate an isomer with two vinylheptafulvene (VHF) units and a cis-azobenzene unit. Ultrafast spectroscopy of the photoisomerizations revealed a fast DHA-to-VHF photoisomerization and a slower trans-to-cis AZB photoisomerization. This meta triad underwent thermal VHF-to-DHA back-conversion with a similar rate of all VHFs, independent of the identity of the neighboring units, and in parallel thermal cis-to-trans AZB conversion. The experimental observations were supported by computation (excitation spectra and orbital analysis of the transitions). 相似文献
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Martina Chirilus‐Bruckner Daniela Maier Guido Schneider 《Mathematische Nachrichten》2019,292(6):1246-1259
We consider a nonlinear diffusion equation on an infinite periodic metric graph. We prove that the terms which are irrelevant w.r.t. linear diffusion on the real line are irrelevant w.r.t. linear diffusion on the periodic metric graph, too. The proof is based on L1‐ estimates combined with Bloch wave analysis for periodic metric graphs. 相似文献
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Journal of Solution Chemistry - The liquid state is one of the three principal states of matter and arguably the most important one; and liquid mixtures represent a large research field of profound... 相似文献
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