Reaction-based fluorescent probe for differential detection of cyanide and bisulfite in the aqueous media

Abstract

A dual-channel fluorescent probe PHTP with excellent water solubility and detection limit was used. The detection selectivity of the probe with CN− or HSO3− was determined by the pH value of the solution. Probe reacted with HSO3− at the pH of solution was 7.4 and emit a fluorescence signal at 450 nm, but probe reacted with CN− at pH of 9.3 and an intense fluorescence emission with a peak at 507 nm was acquired, and mutual interference observed during the response process was scarce. In addition, other competitive biologically relevant species, including F─, Cl─, Br─, I─, NO3─, SO42─, SCN─, H2PO4─, CO32─, C2O42─, AcO─, N3─, NO2─, HCO3─, S2O32─, HS─, Cys, GSH, and Hcy, were also rare interfere. The reaction mechanism was investigated by direct HR-MS, 1H NMR and extensive theoretical calculation. Furthermore, the cytotoxicity of PHTP by the standard MTT assay has been examined, PHTP had good biocompatibility and low cytotoxicity, and the probe was applied in the detection of living cells.