直接进样超高效液相色谱-三重四极杆质谱法快速测定环境水样中草甘膦、氨甲基膦酸、草铵膦及乙烯利残留

建立了一种简便、直接进样的超高效液相色谱-三重四极杆质谱法（UPLC-MS/MS）快速测定环境水样中草甘膦、氨甲基膦酸、草铵膦及乙烯利的残留。环境水样经0.22 μm滤膜过滤或冷冻离心去除杂质后，滤液无需衍生化直接进行定量分析。4种农药通过Metrosep A Supp 5柱（150 mm×4.0 mm，5 μm）分离，以碳酸氢铵-氨水溶液为流动相进行梯度洗脱，在负离子模式下以MRM方式进行检测。结果表明，4种农药在0.50~50.0 μg/L范围内相关系数（r）均大于0.999，线性关系良好，方法检出限为0.05~0.09 μg/L。实际水样在低、中、高3种加标浓度水平下，回收率分别为76.3%~108%、83.0%~107%和87.0%~105%，相对标准偏差分别为2.0%~12.3%、2.4%~5.6%和2.7%~6.8%。使用该方法对海南省34个水样进行测定，其中30个饮用水源地水样中均未检出4种农药，槟榔园附近3个水样均检出草甘膦和氨甲基膦酸，香蕉园附近的1个水样检出草铵膦和氨甲基膦酸。与传统的衍生化方法比较，该方法操作简便，重现性好，准确性高，不受基体干扰，适用于环境水样中草甘膦、氨甲基膦酸、草铵膦及乙烯利的残留检测。

Rapid determination of glyphosate,aminomethyl phosphonic acid,glufosinate, and ethephon residues in environmental water by direct injection-ultra performance liquid chromatography-triple quadrupole mass spectrometry

A simple method based on direct injection-ultra performance liquid chromatography-triple quadrupole tandem mass spectrometry (UPLC-MS/MS) was established for the rapid determination of glyphosate, aminomethyl phosphonic acid, glufosinate, and ethephon residues in environmental water. The water samples were filtered through a 0.22-μm filter membrane or frozen and centrifuged to remove impurities, and then, the filtrate was directly subjected to quantitative analysis without derivatization. The analytes were separated on a Metrosep A Supp 5 column (150 mm×4.0 mm, 5 μm), and gradient elution was carried out using an ammonium bicarbonate-ammonia solution as the mobile phase. The data were collected by positive electrospray ionization in the multiple reaction monitoring (MRM) mode. The results showed that the correlation coefficients (r) of the linear calibration curves were greater than 0.999 in the corresponding linear ranges (0.50-50.0 μg/L). The detection limits of the analytes were 0.05-0.09 μg/L. The recoveries of glyphosate, aminomethyl phosphonic acid, glufosinate, and ethephon were in the ranges 76.3%-108%, 83.0%-107%, and 87.0%-105% at low, medium, and high spiked levels, respectively. The corresponding relative standard deviations were in the ranges 2.0%-12.3%, 2.4%-5.6%, and 2.7%-6.8%. Using this method, 34 water samples collected from Hainan Province were analyzed, among which 30 drinking water sources were found to be free from the four pesticides. Glyphosate and aminomethyl phosphonic acid were detected in three water samples near a betel nut orchard, while glufosinate and aminomethyl phosphonic acid were detected in a water sample near a banana orchard. This method is advantageous over the traditional derivatization method because of its simple operation, good reproducibility, and high accuracy; furthermore, the matrix interference effect is absent. Thus, this method is suitable for analyzing glyphosate, aminomethyl phosphonic acid, glufosinate, and ethephon residues in environmental water samples.