[Determination of acetochlor and its metabolites in urine using liquid chromatography-tandem mass spectrometry].

Objective: A method for the determination of acetochlor and its metabolites in urine by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was established. Methods: After cleaned-up by a HLB extraction cartridges, the urine was eluted with 1% acetic acid acetonitrile solution. The target compounds were separated by ACQUITY UPLC®HSS T3 Column (2.1 mm×100 mm×1.8 μm) by using 1% formic acid solution and acetonitrile as mobile phase with gradient elution program, and analyzed in positive electrospray ionization mode by liquid chromatography tandem mass spectrometry. Results: All the target compounds showed good linear relationships in the range of 1-50 μg/L, and the correlation coefficients (r) were higher than 0.997. The recoveries rates at three different spiked levels for all target compounds in blank matrices were 107.6%-129.1%, and the relative standard deviations (RSD) were 1.5%-9.9% (n=6) . The limits of detection and quantitation of the method were 0.04-0.11 μg/L and 0.15-0.42 μg/L, respectively, and target substances were detected in all urine samples from occupational exposure workers to acetochlor. Conclusion: This method is suitable for rapid screening and analysis of acetochlor and metabolites in urine with the advantages of accuracy, rapidity, simplicity, high sensitivity and good specificity.目的： 建立了液相色谱-串联质谱法（LC-MS/MS）测定尿样中乙草胺及其3种代谢物。 方法： 于2021年4月，尿液经HLB小柱净化，1%乙酸乙腈溶液洗脱。以0.01%甲酸溶液-乙腈作为流动相，梯度洗脱，目标物使用ACQUITY UPLC®HSS T3色谱柱（2.1 mm×100 mm×1.8 μm）作为分离柱，采用LC-MS/MS在正离子模式下进行测定。 结果： 4种目标物在1~50 μg/L范围内线性关系良好，相关系数（r）均>0.997，各目标物质在空白尿样中3个浓度添加水平下的回收率为107.6%~129.1%，相对标准偏差（RSD）为1.5%~9.9%（n=6），方法检出限和定量限分别为0.04~0.11 μg/L和0.15~0.42 μg/L。乙草胺职业接触人群尿样中所有目标物均有检出。 结论： 该方法操作简单、快速、灵敏度高、特异性好，适用于尿样中乙草胺及其代谢物浓度的快速检测。.