农产品中基质对酶联免疫分析法检测三唑磷残留的干扰及消除研究(英文)

Investigation of interference from agricultural sample with ELISA for the residue determination of triazophos and circumventing matrix effects

基质干扰是免疫法检测食品中农药残留时经常碰到的问题。以胡萝卜、菠菜、香蕉、梨、稻米和花生等为试材,研究了不同农产品基质对酶联免疫分析法(ELISA)检测三唑磷的影响。结果表明:不同农产品基质对ELISA检测的干扰机制不同,香蕉主要是抑制了辣根过氧化物酶的活性,菠菜、梨和稻米则主要是干扰了抗原和抗体的结合反应,胡萝卜和花生不仅抑制酶的活性,同时还干扰了抗原和抗体的结合反应。将这些农产品的磷酸盐缓冲液(PBS)(含2.5%甲醇)提取液用含有质量分数为0.3%的脱脂奶粉、0.1%的乙二胺四乙酸(EDTA)和含2.5%甲醇的PBS稀释10倍,在12 000 r/min下离心10 min,即可消除其对ELISA检测的干扰。研究结果表明,ELISA法是可用于农产品中三唑磷残留检测的一种简单、快速、有效的方法。

Matrix interference is a common challenge for pesticide analysis in food by immunoassay.Carrot,spinach,banana,pear,rice grain and peanut w ere selected to investigate the matrix interference w ith ELISA for triazophos.The results indicated that matrix interference from banana primarily inhibited enzyme activity,and spinach,pear,rice grain mainly hindered antigen and antibody interaction.For carrot and peanut samples,matrixes interfered w ith not only enzyme activity,but also antigen and antibody interaction.When agricultural sample extracts w ere diluted ten-fold w ith 0.3% skimmed milk,0.1mmol / L EDTA,2.5% methanol PBS follow ed by a centrifugation at 12 000 r / min for 10 min,the matrix effect can be eliminated.The results confirmed that ELISA is suitable for the residue determination of triazophos in agricultural samples as a simple,effective method.