Abstract:

In order to generate a monoclonal antibody (McAb) against sulfadianzine (SD), three separate immunogens with SD/BSA conjugation ratios of 9.0, 8.0 and 3.7 were prepared by diazotization method and BALB/c mice were then immunized with the immunogens. An optimum immunization was observed in BALB/c mice immunized with the immunogen with middle SD/BSA conjugation ratio. A McAb (1F6) with high affinity to SD was obtained by hybridoma technique. The titer of the McAb was 1:1.28 ×106 in ascites according to the indirect ELISA determination. IC50 and the lowest detectable limit (LDL) of the McAb in linear range of 14.8－421.5 ng/mL for SD were 79.1 ng/mL and 10.4 ng/mL, respectively. The cross-reactivity ratios of the McAb against sulfamethazine, sulfamonomethoxine and sulfamethoxydiazine were 0.3%, 0.99% and 4.5%, respectively, while no cross-reactivity to sulfamethoxazole, sulfaquinoxaline, 4-aminobenzoic acid, sulfanilamide or sulfanilic acid was observed. The sub-class of the McAb was identified as IgG2b.

Key words: sulfadiazine, diazotization, ELISA, monoclonal antibody