In this paper, a new chemiluminescence method for measuring free HRP and labeled HRP is developed by coupling the reaction of H~2O~2-KI catalyzed by HRP with the chemiluminescence reaction of luminol-I~2. The detection limits of HRP is 7 pg/tube and the RSD for 20pg/tube HRP (n=11) is 7.5%. The method hold the linear relationship for HRP over 10-6000pg/tube. Comparison of coupling reaction chemiluminescence method and the direct luminol-H~2O~2 chemiluminescence method of HRP shows that the coupling reaction method is 3 times and 10-100 times more sensitive for free HRP and for labeled HRP. The mechanism and kineties characteristic of the coupling reaction has been studied.

Key words: DETERMINATION, CHEMILUMINESSENCE, HYDROGEN PEROXIDE, POTASSIUM IODIDE, ANTIBODY, COUPLING REACTION, MECHANISM, DYNAMICS