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We report herein the photoinduced electron/energy transfer–reversible addition‐fragmentation chain transfer (PET‐RAFT) polymerization of styrene‐maleic anhydride (SMAnh) using the photocatalyst, zinc tetraphenylporphirine, under a white cool LED light. PET‐RAFT is an easy and convenient polymerization method that does not require deoxygenation unlike other radical polymerizations. Various parameters, for example, the amount of styrene in the feed or the solvent, and their influence on the polymerization were studied. After hydrolysis of the anhydride moieties, the resulting styrene‐maleic acid (SMA) copolymers obtained by PET‐RAFT copolymerization were evaluated for their solubilization efficiency of three different membrane proteins, BmrA and AcrB, overexpressed in Escherichia coli, and A2AR, expressed in insect cells (Sf9). The different copolymers provided similar solubilization rates to the commercially available SMA; however, a highly improved migration behavior on sodium dodecyl‐sulfate polyacrylamide gel electrophoresis was observed which could, facilitate downstream analyses. Overall, we demonstrated that PET‐RAFT is a versatile oxygen tolerant polymerization technique to yield SMA, a suitable polymer for biochemical applications. [ABSTRACT FROM AUTHOR]

The fluorescence properties of four derivatives of 3-thienyl-2-(N-dicyanovinyl)iminocoumarin, bearing a diethylamino group in the 7-position or a methoxy group in the 6, 7 and 8 positions, were compared in solution and in the solid state. The 7-diethylamino derivative was strongly fluorescent in various solvents, with marked solvatochromism. Its fluorescence was quenched by aggregation. In contrast, the methoxy derivatives were only moderately or weakly fluorescent in solution, but two of them were strongly photoluminescent in the crystalline state, owing to favourable molecular packing. The 6-methoxy derivative even exhibited spectacular crystallization-enhanced emission, examples of which are particularly rare for this type of dyes. Dyes were tested for biological use. The 7-diethylamino derivative led to particularly strong fluorescence staining of the cytoplasm of HCT-116 colon cancer cells. No fading was observed over prolonged illumination by the microscope light beam, but a phototoxic effect was detected. The use of the dyes as red-emitting materials was also investigated. Using easy-to-implement preparation methods, the compounds self- assembled to give one-dimensional nano- and microsized particles, including millimeter-long microfibres that exhibited clear wave-guiding properties. This study shows the value of these low molecular-weight molecules for the preparation of new orange and red-emitting fluorescent materials based on totally pure dye., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A series of europium and terbium complexes based on a functionalized triazacyclononane carboxylate or phosphinate macrocyclic ligand is described. The influence of the anionic group, that is, carboxylate, methylphosphinate, or phenylphosphinate, on the photophysical properties was studied and rationalized on the basis of DFT calculated structures. The nature, number, and position of electron-donating or electron-withdrawing aryl substituents were varied systematically within the same phenylethynyl scaffold in order to optimize the brightness of the corresponding europium complexes and investigate their two-photon absorption properties. Finally, the europium complexes were examined in cell-imaging applications, and selected terbium complexes were studied as potential oxygen sensors., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)