胶体金免疫层析法快速检测食品中的米酵菌酸

The Rapid Detection of Bongkrekic Acid in Foods Using Colloidal Gold Immunochromatographic Assay

制备特异性识别米酵菌酸的单克隆抗体,并以胶体金标记用作示踪物,建立胶体金免疫层析快速检测方法。研究胶体金标记体系pH值、抗原、抗体质量浓度、离子强度、表面活性剂以及样品前处理方法等对胶体金层析卡性能的影响。结果表明:在最适条件下,所建立的胶体金免疫层析方法对米酵菌酸的定量检出限为1.2μg/kg,线性范围1.8~7.2μg/kg,定性检出限16.0μg/kg。该方法特异性良好,与食品中常见的毒素无交叉反应,对银耳、木耳和米粉等样品的添加回收率在80.2%~101.2%之间,相对标准偏差小于6.4%,且结果与LC-MS/MS法一致。该方法具有准确、灵敏、简便、快速和低成本等特点,可以满足食品中米酵菌酸现场大批量筛查的需求。

In this study,a specific monoclonal antibody against bongkrekic acid(BA)was produced.The antibody was conjugated to colloidal gold as a tracer to develop a colloidal gold immunochromatography assay(GICA).The effect of working conditions,including pH value of labeling,mass concentrations of antibody and antigen,ionic strength,surfactant as well as sample pretreatment on GICA performance were studied.Under the optimal condition,the developed GICA showed a quantitative limit of detection of 1.2μg/kg,a detection range of 1.8-7.2μg/kg,and a qualitative detection limit of 16.0μg/kg,respectively.The proposed assay has shown good specificity,and exhibited no cross-reaction with other toxins commonly found in food.Recovery test was done by using tremella,agaric,and rice flour samples and ranged from 80.2%to 101.2%with the relative standard deviation(RSD)less than 6.4%.Besides,the results had good agreement with that of liquid chromatography-tandem mass spectrometry(LC-MS/MS).In conclusion,the proposed assay can meet the demand for mass screening of bongkrekic acid in food in an accurate,sensitive,convenient,rapid,and low-cost manner.