PREPARATION OF ESTRADIOL COMPLETE ANTIGEN AND ANTI-ESTRADIOL POLYCLONAL ANTIBODY

Object To modify estradiol(E2) hapten,to synthesize complete antigens,and to immunize two rabbits for preparing anti-estradiol polyclonal antibody,so as to provide the foundation for rapid detection of E2 residue in animal food by Enzyme-Linked Immunosorbent Assay.Methods Estradiol was modified to be estradiol hapten(E2-3-CME).Complete antigens,immunogen(E2-BSA) and coating antigen(E2-OVA),were synthesized by coupling with carrier proteins(BSA and OVA) using carbodiimide method(EDC method).The conjugates were identified by SDS-PAGE and mass spectrography.The polyclonal antibody was obtained by two rabbits' immunization,and the titre,sensitivity and specificity of serum were evaluated by ELISA.Results The immunogen and coating antigen of estradiol were synthesized successfully.After the sixth immunization,the titre of antiserum from two rabbits reached 1∶128 000,1∶32 000 respectively,and the half inhibition concentration(IC50) was 44.00 ng/ml,and 45.59 ng/ml respectively.Both of the polyclonal antibodies had no conspicuous cross-reaction with the other analogues.Conclusion The estradiol complete antigen so synthesized has good immunogenicity and the polyclonal antibodies obtained are highly specific.