Production of a monoclonal antibody against oxytetracycline and its application for oxytetracycline residue detection in shrimp.

A novel monoclonal antibody (MAb) against oxytetracycline (OTC) was generated and characterized. The MAb was used in the development of an enzyme-linked immunosorbant assay (ELISA)-based detection system. An OTC-bovine serum albumin (BSA) conjugate was prepared and used in the immunization of mice. A conventional somatic cell fusion technique was used to generate MAb-secreting hybridomas denoted 2-4F, 7-3G, and 11-11A. An indirect competitive ELISA (icELISA) was applied to measure the sensitivity and specificity of each MAb in terms of its 50% inhibitory concentration (IC50) and percentage of cross-reactivity, respectively. MAb 2-4F exhibited the highest sensitivity, with an IC50 of 7.01 ng/ml. This MAb showed strong cross-reactivity to rolitetracycline, but no cross-reactivity to other unrelated antibiotics. When MAb 2-4F was used to detect OTC from shrimp samples, the recoveries were in the range of 82%-118% for an intra-assay and 96%-113% for an inter-assay. The coefficients of variation of the assays were 3.9%-13.9% and 5.5%-14.9%, respectively.