Surfactant-induced modification of quenching of conjugated polymer fluorescence by electron acceptors: applications for chemical sensing

Both the photophysics and the fluorescence quenching behavior of an anionic conjugated polymer towards various small molecule quenchers can be modulated effectively by complexing the polymer with a simple countercharged detergent. For example upon adding odecyltrimethylammonium bromide (DTA) to the polymer, cationic quenchers such as methyl viologen become less effective while the quenching by neutral reagents – most notably nitroaromatics or cyanoaromatics – is enhanced. Thus, the polymer–detergent complex provides a new platform for sensing chemical agents via fluorescence quenching. Thin films formed from the complex exhibit high sensitivity to quenching by nitroaromatic vapor and reasonable reversibility.