A multi-responsive diarylethene-rhodamine 6G derivative for sequential detection of Cr3+ and CO32−

Abstract

A new unsymmetrical diarylethene derivative (1o) with rhodamine 6G as a functional group has been designed and synthesized. It displayed good physicochemical properties induced by lights and chemical stimuli. 1o could sensitively detect towards Cr3+ with a 1:1 stoichiometry, and exhibit an obviously fluorescence (from dark to light cyan) and color (from colorless to pink) changes during the recognition process. The limit of detection was determined to be 27 nM and 8.5 nM via UV/vis and fluorescence methods, respectively. More importantly, the resulting complex 1o-Cr3+ (1o') could be served as a potential fluorescent probe to selectively and sensitively recognize toward CO32−, the limit of detection was determined to be 0.88 μM and 0.26 μM via UV/vis and fluorescence methods, respectively. Moreover, the quenching of fluorescence intensity can reach 95% due to the perfect FRET processes between the excited open-ring rhodamine 6G moiety and the closed-ring diarylethene unit.