Development of a novel rhodamine-type fluorescent probe to determine peroxynitrite

A novel method for the determination of peroxynitrite using rhodamine B hydrazide as a fluorogenic probe is described. The method is based on the oxidation of rhodamine B hydrazide, a colorless, non-fluorescent substance, by peroxynitrite to give rhodamine B-like fluorescence emission. The fluorescence increase is linearly related to the concentration of peroxynitrite in the range of 7.5×10 −8 –3.0×10 −6 mol l −1 with a detection limit of 2.4×10 −8 mol l −1 (3 σ ). The optimal conditions for the detection of peroxynitrite were evaluated and the possible detection mechanism was also discussed in this paper.