Yang H H, Zhu Q Z, Li D H, Lin P, Ding M T, Xu J G
Department of Chemistry, Xiamen University, P.R. China.
Fresenius J Anal Chem. 2001 May;370(1):88-91. doi: 10.1007/s002160100723.
A new fluorimetric immunoassay for alpha-fetoprotein (AFP) has been developed using a novel promising mimetic peroxidase, iron(III) tetrasulfonatophthalocyanine (FeTSPc), as a labeling reagent to catalyze the fluorescence reaction of P- hydroxyphenylacetic acid (P-HPA) and hydrogen peroxide (H2O2). In the competitive immunoassay, anti-AFP antibody was coated on a 96-well plate (polystyrene) and a constant amount of FeTSPc-labeled AFP and a known amount of test solution were added. Non-labeled and FeTSPc-labeled AFP compete for binding to the plate-bound antibody. After the immunoreaction, the immunochemically adsorbed FeTSPc-AFP conjugate moiety was determined by measuring the fluorescence produced in a solution containing P-HPA and H2O2. AFP can be determined in the concentration range of 1-300 ng mL(-1) with a detection limit of 0.5 ng mL(-1).