化学发光免疫分析方法检测粮食谷物中赭曲霉毒素A残留

摘要

目的 建立粮食谷物中赭曲霉毒素A(ochratoxin A,OTA)残留检测的化学发光免疫分析方法.方法 人工改造OTA半抗原、制备包被原和多克隆抗体工作液,优化检测步骤,验证各项评价指标,比较化学发光免疫分析方法和高效液相色谱法(high performance liquid chromatography,HPLC)的实际样本检测结果的一致性,以此来实现化学发光免疫分析方法的建立.结果 50％抑制浓度(IC50)为0.278 μg/L;OTA的最低检出限为5.0 μg/kg,样本添加回收率在65.4％到115.8％之间,批内、批间相对标准偏差＜15％.同时,通过对实际样本检测,证明化学发光免疫分析方法具有显著的准确度和可靠性.结论 基于化学发光免疫分析方法能够实现粮食作物中的OTA残留的快速检测,灵敏度高、成本低、时间短,为食品中霉菌毒素残留的快速检测提供了新的技术参考.%Objective To establish a method for determination of ochratoxin A residues in grains and cereals by chemiluminescence immunoassay.Methods The ochratoxin A hapten was engineered to prepare the coating solution of the original and polyclonal antibody.The detection procedure was optimized and the evaluation indexes were validated.The consistency of the actual sample test results was compared between chemiluminescence immunoassay method and high performance liquid chromatography (HPLC) in order to achieve the establishment of chemiluminescence immunoassay.Results The 50％ binding inhibition (IC50) values of the method were 0.278 μg/L for ochratoxin A under optimum conditions.The recoveries ranged from 65.4％ to 115.8％,the intra-assay and inter-assay coefficients of variation were less than 15％.The limits of detection (LODs) for the assay were 5.0 μg/kg.Finally,grains and cereals samples were analyzed by chemiluminescence immunoassay,and the results correlated well with those obtained using traditional ELISA and HPLC.Conclusion Chemiluminescence immunoassay has been proved to be an effective analytical technique for using in ochratoxin A monitoring owing to its high sensitivity,low cost and ease of handling,which provides a new technical reference for the rapid detection of mycotoxins residues in food.