Abstract: Clenbuterol is a small molecular hapten that has immunoreactivity but hasn’t immunogenicity. It is coupled with bovine serum albumin by diazotization in this article. And the Clenbuterol_BSA conjugate is identified by ultra violet scan, SDS- PAGE and indirect inhibited ELISA .The results demonstrated that the Clenbuterol_BSA conjugate has immunogenicity which is good for next monoclonal antibody preparation and the research of ELISA kit .

Key words:  Clenbuterol, diazotion, conjuate