Design of activatable red-emissive assay for cysteine detection in aqueous medium with aggregation induced emission characteristics

A novel wate r-soluble red-emissive AIE fluorescence probe for cysteine(Cys) in situ was prepared and the performance of selectivity and sensitivity has been carefully investigated in this study.The probe was established on the electrostatic interaction of sulfonate functionalized tetraphenylethene(TPE) and polycation generated by the reaction between a polymer bearing dinitrobenzenesulfonate groups and Cys.From the experimental results,it was easy to distinguish Cys from glutathione(GSH) and homocysteine(Hcy) with a detection limit of 73 nmol/L.The assay system also possessed strong antiinterference ability against multitudinous amino acids.The Stokes shift was 142 nm and the emission ranged from 550 nm to 850 nm.In addition,double responses in fluorescence and ultraviolet-visible spectra also make the red-emissive assay ideal for sensitive detection and quantification of Cys for most purposes,especially in-situ monitoring of Cys in aqueous medium.