Abstract:

【Objective】 The purpose of the study is to obtain special antibody and develop competitive indirect enzyme-linked immunosorbent assay (ciELISA) for florfenicol 【Method】 Florfenicol hapten was conjugated with the carrier proteins bovine serum albumin (BSA) as immunogen and with human serum albumin (HSA) as coating antigen, respectively, and the coupling ratio of FFC-HS-BSA was 14.4 and the coupling ratio of FFC-HS-HSA was 14.7. Polyclonal antibody against florfenicol was generated by immunizing rabbits with FFC-HS-BSA. 【Result】 The antiserum with high titer was 1﹕102 400. The indirect competitive ELISA revealed that the optimal concentration of rabbit serum was 1﹕6 400, the optimal concentration of coated antigen was 0.5 μg?ml-1, and the optimal concentration of sheep anti-rabbit IgG was 1﹕20 000. The regression equation was Y=－0.1516X + 0.788 (R2=0.9859), the lowest detection limit was 0.18 ng?ml-1, the linear range was from 0.18 ng?ml-1 to 500 ng?ml-1, and the coefficients of variation of intra-assay and inter-assay were respectively 4.86% and 7.77%. The antiserum had cross reactivity of 0.094% and 0.098% with chloramphenicol and thiamphenicol, respectively, but had cross reactivity of less than 0.01% with others. The recoveries in chicken ranged from 84.14% to 106.1%. 【Conclusion】 The antibodies with high titer and specificity were produced successfully and a competitive indirect enzyme-linked immunosorbent assay (ciELISA) was developed for the detection of florfenicol residue in chicken. The results showed that the method is sensitive, accurate, convenient, and quick.

Key words: florfenicol, residue detection, indirect competitive ELISA