Immunogenicity of Novel Sulfadimethoxide Conjugates

Sulfadimethoxine (SDM) is an antibiotic commonly added to animal feeds. Anti-SDM antibodies are useful for the detection of residual SDM in foods, feeds and biological fluids by ELISA. In this study, we show that SDM is immunogenic in rabbits when it is conjugated with soy 11S globulin or with beta-amylase. Rabbit anti-SDM antibodies obtained by immunization with SDM-11S and SDM-beta-amylase displayed low cross-reactivity against other sulfonamides, including sulfamethazine (SM2), sulfasulfonamides (SN), sulfadiazine (SD), sulfamethoxypyrazine (SMP), sulfalene (SMZ), sulfaquinoxaline (SQX). Thus, soy 11S globulin and beta-amylase are suitable carriers for the induction of anti-SDM antibodies and have the advantage of being cheaper that BSA.