Investigation on the potential use of the mimetic peroxidase-catalyzed reaction of hydrogen peroxide and o-hydroxyphenylfluorone in fluorescence analysis

The reaction between o-hydroxyphenylfluorone (HPF), a common fluorescence d ye, and hydrogen peroxide catalyzed by mimetic peroxidase iron-telrasulfona tophthalocyanine (FeTSPc) has been adapted to the determination of trace am ounts of H2O2, FeTSPc and FeTSPc-mouse immunoglobulin G (IgG) conjugate. In the case of catalysis with FeTSPc, trace amounts of H2O2 can quench the fl uorescence of HPF rapidly and significantly. Under optimum conditions, the logarithm value of fluorescence quenching (log(F-0/F)) was linear over the range of 0.0-1.0 x 10(-7) mol/l H2O2, 0.0-9.0 x 10(-8) mol/l FeTSPc and 0.0 -8.0 x 10(-8) mol/l FeTSPc-IgG conjugate, with the detection limits of 7.5 x 10(-10) mol/l H2O2, 7.0 x 10(-10) mol/l FeTSPc and 2.6 x 10(-10) mol/l Fe TSPc-IgG conjugate, respectively. The catalytic activity of FeTSPc increase d by more than three times when it was labeled to IgG. The feasibility of a pplying the catalyzed system in the environmental detection of trace amount s of H2O2 was also studied. The proposed FeTSPc-catalyzed system was conclu ded as being suitable for both H2O2 determinations and mimetic enzymatic im munoassays. (C) 2000 Elsevier Science B.V. All rights reserved.