A simple but effective fluorescent probe for the detection of bisulﬁte
A new fluorescence probe (PML) based on Michael addition reaction for sensing HSO3- was developed. The probe was composed of carbazole and 2-(3-cyano-4,5,5-trimethylfuran-2(5H)-ylidene)malononitrile moieties and can be easily synthesized. The carbazole-based probe can selectively detect HSO3- and shows good sensitivity with the limit of detection of 2.08×10-6 M in PBS: DMF = 1: 1 buffer solution. Upon addition of HSO3-, the intense fluorescence of probe was quenched and the color changed markedly from red to colorless. In addition, the probe can be used to detect HSO3- in dry white wine.