Turn-on mode fluorescent diarylethene containing neopentyl substituents that undergoes all-visible-light switching.

This paper presents a strategy for improving the all-visible-light switching response of turn-on mode fluorescent diarylethene derivatives. Introduction of neopentyl or isobutyl substituents at the reactive carbons (2- and 2'-positions) of an oxidized bis(benzothienyl)perfluorocyclopentene derivative, which undergoes both cyclization and cycloreversion reactions upon irradiation with visible light, was effective in increasing the cycloreversion quantum yield by one or two orders of magnitude in comparison with the yield of an ethyl-substituted derivative. Any significant influence on the cyclization and fluorescence quantum yields was not observed by the introduction of neopentyl or isobutyl substituents.

Cytotoxicity and colloidal behavior of polystyrene latex nanoparticles toward filamentous fungi in isotonic solutions.

The effects of surface physicochemical properties of functionalized polystyrene latex (PSL) nanoparticles (NPs) and model filamentous fungi Aspergillus oryzae and Aspergillus nidulans cultivated in different environment (aqueous and atmospheric environment) on the colloidal behavior and cytotoxicity were investigated in different isotonic solutions (154 mM NaCl and 292 mM sucrose). When the liquid cultivated fungal cells were exposed to positively charged PSL NPs in 154 mM NaCl solution, the NPs were taken into A. oryzae, but not A.