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861.
862.
Dr. Irena Senkovska Dr. Volodymyr Bon Dr. Leila Abylgazina Dr. Matthias Mendt Jan Berger Dr. Gregor Kieslich Prof. Petko Petkov Jhonatan Luiz Fiorio Dr. Jan-Ole Joswig Prof. Thomas Heine Larissa Schaper Christopher Bachetzky Prof. Rochus Schmid Prof. Roland A. Fischer Prof. Andreas Pöppl Prof. Eike Brunner Prof. Dr. Stefan Kaskel 《Angewandte Chemie (International ed. in English)》2023,62(33):e202218076
Flexible porous frameworks are at the forefront of materials research. A unique feature is their ability to open and close their pores in an adaptive manner induced by chemical and physical stimuli. Such enzyme-like selective recognition offers a wide range of functions ranging from gas storage and separation to sensing, actuation, mechanical energy storage and catalysis. However, the factors affecting switchability are poorly understood. In particular, the role of building blocks, as well as secondary factors (crystal size, defects, cooperativity) and the role of host–guest interactions, profit from systematic investigations of an idealized model by advanced analytical techniques and simulations. The review describes an integrated approach targeting the deliberate design of pillared layer metal–organic frameworks as idealized model materials for the analysis of critical factors affecting framework dynamics and summarizes the resulting progress in their understanding and application. 相似文献
863.
864.
Franziska Hausig-Punke Gregor Dekevic Fabian H. Sobotta Jana I. Solomun Friederike Richter Denise Salzig Anja Traeger Johannes C. Brendel 《Macromolecular bioscience》2023,23(5):2370016
Cationic pH-responsive polymers promise to overcome critical challenges in cellular delivery. Ideally, the polymers become selectively charged along the endosomal pathway disturbing only the local membrane and avoiding unintended interactions or cytotoxic side effects at physiological conditions. Polypiperazines represent a novel, hydrophilic class of pH-responsive polymers whose response can be tuned within the relevant pH range (5–7.4). The authors discovered that the polypiperazines are effectively binding plasmid DNA (pDNA) and demonstrate high efficiency in transfection. By design of experiments (DoE), a wide parameter space (pDNA and polymer concentration) is screened to identify the range of effective concentrations for transfection. An isopropyl modified polypiperazine is highly efficient over a wide range of concentrations outperforming linear polyethylenimine (l-PEI, 25 kDa) in regions of low N*/P ratios. A quantitative polymerase chain reaction (qPCR) surprisingly revealed that the pDNA within the piperazine-based polyplexes can be amplified in contrast to polyplexes based on l-PEI. The pDNA must therefore be more accessible and bound differently than for other known transfection polymers. Considering the various opportunities to further optimize their structure, polypiperazines represent a promising platform for designing effective soluble polymeric vectors, which are charge-neutral at physiological conditions. 相似文献