Abstract: Objective To develop an easy to use,rapid and accurate test to detect cocaine and its benzoylecgonine by the col-loidal gold immunochromatographic assay.Methods Anti-cocaine,monoclonal antibodies were conjugated with colloidal gold particles.The complete antigen cocaine-BSA was coated on the nitrocellulose membrane as the test line T.Different intensities of the purple lines on the strip could be seen as a result of the competition for binding to the conjugated antibodies between the complete antigens and free cocaine and benzoylecgonine which may be present in the samples.Results The cocaine test cas-sette can detect cocaine and benzoylecgonine in 5 minutes without any cross reactions to other kind of drugs.One hundred and seventy urine samples were tested by immunochromatographic cassette and GC/MS methods,and the accuracy for cocaine and benzoylecgonine was 98.9% and 98.6%,respectively.The cut-off value was established to be 300ng/ml for cocaine and ben-zoylecgonine.The stability experiment showed that the cocaine test cassette can maintain its effect for at least one month at 45℃.Conclusion The reported cocaine immunochromatographic test cassette is a sensitive,specific,rapid and easy to use as-say for detecting cocaine and benzoylecgonine in samples.

Key words: forensic toxicological analysis, cocaine, benzoylecgonine, colloidal gold, monoclonal antibody

摘要： 目的根据胶体金免疫层析的原理,建立一种可以在现场快速检测可卡因及其代谢物苯甲酰爱康宁的方法。方法将胶体金标记的抗可卡因单克隆抗体均匀浸涂在玻璃纤维膜上,用点膜仪将可卡因的完全抗原以及羊抗鼠多抗在硝酸纤维素膜上划线,分别作为可卡因的检测区(T)和质控区(C)。并且对样品垫用0.2%Tween 20和0.5%PVA封闭处理。样本(尿样、唾液、血样等)中游离的可卡因及其代谢物同包被的完全抗原分别免疫竞争结合胶体金标记的抗可卡因单抗。肉眼观察试剂盒的质控区和检测区上有无紫红色带来判读结果。结果可卡因胶体金检测试剂盒对65种毒品、药物的特异性测试中仅识别可卡因及其代谢物。对人体尿样中的可卡因和苯甲酰爱康宁检测阈值均为300ng/mL。与GC/MS对照试验,其准确性分别为98.9%和98.6%。在常温下能稳定保存2年。结论该可卡因检测试剂盒在5min内可以检测出样本中的可卡因及其代谢物成分。

关键词: 法医毒物分析, 可卡因, 苯甲酰爱康宁, 胶体金, 单克隆抗体