Abstract: In this study, a capillary electrophoresis immunoassay(CEIA) method based on the enhanced chemiluminescence(CL) detection was developed. A horseradish peroxidase(HRP) label catalyzing the luminol/H₂O₂/p-iodophenol(PIP) reaction was performed, and the HRP was detected with detection limit(S/N=3) of 4.4 pmol/L(53 zmol), which is one of the highest sensitivity of HRP reported yet. The HRP was linked to bone morphogenic protein-2(BMP-2) in rat vascular smooth muscle(VSM) cells in noncompetitive format and first detected by CL. HRP-Ab₆-mAb-BMP-2 complexes were baseline separated from free HRP label in 3 min. The detection limit(S/N=3) of BMP-2 is 6.2 pmol/L(75 zmol). This technique has been applied to arteriosclerosis pathology research. The change of BMP-2 contentin VSM cells which were stimulated by angiotensin Ⅱ(AgⅡ) for different hours was investigated in the concentration range of 1.0-10.0 pmol/L. The results are in accord with that obtained by common used Pathology image analysis system.

Key words: Capillary electrophoresis, Chemiluminescence, Immunoassay, Antigen antibody, Bone morphogenic protein-2