A novel fluorescent method for determination of peroxynitrite using folic acid as a probe

A novel method for the determination of peroxynitrite using folic acid as a fluorescent probe is described. The method is based on the oxidation of the reduced, low-fluorescent folic acid by peroxynitrite to produce a high-fluorescent emission product. The fluorescence increase is linearly related to the concentration of peroxynitrite in the range of 3 x 10(-8) to 5.0 x 10(-6) mol L-1 with a correlation coefficient of 0.998, and the detection limit is 1 x 10(-8) mol L-1. Interferences from some metal ions normally seen in biological samples, and also some anions structurally similar to peroxynitrite were studied. The optimal conditions for the detection of peroxynitrite were evaluated. (C) 2007 Elsevier B.V. All rights reserved.