A highly selective fluorescent and colorimetric chemosensor for Hg2+ based on a new rhodamine derivative

摘要

The design and synthesis of a novel chemosensor 1 based on rhodamine B and 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) and its application in fluorescence and colorimetric detection of Hg2+ in aqueous solution are reported. The signal change of the chemosensor 1 is based on a specific metal ion induced ring-opening mechanism of the rhodamine spirolactam. It exhibits a high sensitivity and selectivity for the detection of Hg2+ over other tested metal ions in CH3CN : H2O = 1 : 1, and the detection limit can reach 120 nM. In addition, the effects of co-existing metal ions and pH are also investigated. The data obtained clearly indicate that 1 could be used as an excellent chemosensor for Hg2+ detection in environmental samples.