SPE-GC/MS法同时检测地表水中6种常见农药残留物

Automatic SPE-GC/MS Method for the Determination of 6 Common Pesticide Residuals in Water

建立了全自动固相萃取-气质联用法检测地表水中的百菌清、马拉硫磷、联苯菊酯、甲基内吸磷、莠去津、对硫磷6种常见农药残留物的方法。采用HLB固相萃取柱用于水样的富集和净化;地表水样品以6 mL/min的流速上样,然后用5 mL乙腈和10 mL二氯甲烷依次洗脱;洗脱液氮气吹至近干,用1 mL丙酮溶解残渣,过滤;采用气质联用仪对样品进行定性定量检测。6种农药残留物质量浓度在0.03～3.0μg/mL范围内线性关系良好,线性相关系数≥0.995;加标回收率均在81.2%～108.3%之间;检出限如下:百菌清0.008μg/mL,马拉硫磷0.008μg/mL,联苯菊酯0.005μg/mL,甲基内吸磷0.010μg/mL,莠去津0.010μg/mL,对硫磷0.008μg/mL。检测精密度(n=6)的RSD范围为1.47%～4.87%,方法重复性(n=6)相对标准偏差(RSD)在3.10%～4.97%之间。试验表明,该方法自动化程度较高,灵敏度好,准确度高,适用于地表水中多种农药残留物的同时检测。

A automatic solid phase extraction GC/MS method for determination of chlorothalonil,malathion, bifenthrin,demeton-S-methyl,atrazine and parathion in water was established.Samples were enriched and purified by HLB solid phase extraction column,with the rate of 6 mL/min.Then samples were eluted by 5 mL acetonitrile and 10 mL successively.Eluted solution was collected and blowed to near dry.1 mL acetone was used to dissolute residue,then filtered.GC/MS was used to determinate samples qualitatively and quantitatively.Six pesticide residuals showed good linear relationships in the range of 0.03-3.0μg/m L,with which the correlation coefficients were all above 0.995.The recoveries were ranged from 81.2%-108.3%.The detection limits of 6 pesticide residuals were as follows:chlorothalonil 0.008μg/m L,malathion 0.008μg/m L,bifenthrin 0.005μg/m L,demeton-S-methyl 0.010μg/m L,atrazine 0.010μg/m L,and parathion 0.008μg/m L,respectively.RSDs of precision of 6 pesticide residuals were 1.47%-4.87%(n=6),and repeatability was among 3.10%-4.97%.This method was proved to be with high automation,good precision and accuracy,which could be used to determine multiple pesticide residuals in water.