Abstract：The immunoassay method to detect genetically modified (GM) rape(Brassica campestris ) containing the phosphinothricin acetyltransferase (PAT) were developed and applied. The purified PAT was identified by Western blot and enzymic activity analysis. The polyclonal antibody against purified PAT protein was obtained and purified by both saturated ammonium sulfate method and protein A-Sepharose 4B. The sensitivity and cross-reactivity of polyclonal antibody has been demonstrated in ELISA test. The result of the ELISA for antiserum sensitivity was about 2×10-5 mg/mL and the cross-reactivity determined experimentally showed a high degree of specificity for the antiserum used, because values were all less than 0.1 %. The detections of transgenic plants were evaluated with two transgenic rapes (MS1/RF1 and MS8/RF3) and the transgenic rapes (MS1/RF1 and MS8/RF3) could be easily distinguished by ELISA.
