Amphiphilic ESIPT benzoxazole derivatives as prospective fluorescent membrane probes
作者:Priscila Franken Dick、Felipe Lange Coelho、Fabiano Severo Rodembusch、Leandra Franciscato Campo
DOI:10.1016/j.tetlet.2014.03.103
日期:2014.5
Fluorescent amphiphilic benzoxazole derivatives were synthesized and used to produce photoactive phosphatidylcholine (PC) liposomes by reserve-phase evaporation. The dyes absorbed in the UV region and were fluorescent in the blue-green region (determined by solvent polarity). The alkyl chain length seemed to play a fundamental role in the photophysics of the benzoxazole fluorophore in reverse liposomes, and despite the same ESIPT core and phospholipid building block, each amphiphilic dye had a particular emission profile related to the dye location in the liposome. The fluorescence emission spectra from dye 5 showed that its fluorophore experienced a polar environment, due to the single normal emission, while dyes 6-7 had (in part) a normal emission, and the main fluorescent band ascribed to the ESIPT emission indicated a more hydrophobic environment. Despite the complex fluorescent profiles, the benzoxazole derivatives could be successfully introduced into the reverse liposome structure due to the interaction between the alkyl chain and PC bilayer. (c) 2014 Elsevier Ltd. All rights reserved.