建立了固相萃取净化-超高效液相色谱-三重四极杆质谱法测定土壤中草铵膦、草甘膦及其代谢物氨甲基膦酸含量的方法。将土壤样品与水、二氯甲烷混合后，高速匀浆1 min后离心，取上清液3 mL过Oasis HLB固相萃取小柱，收集最后1 mL的流出液，过0.22 μm滤膜。用超高效液相色谱-三重四极杆质谱测定滤液中的草铵膦、草甘膦及其代谢物氨甲基膦酸含量。在色谱分析中，以不同体积比的5 mmol·L^-1的乙酸铵（用氨水调节pH至12）和乙腈的混合溶液为流动相进行梯度洗脱，以Dikma Polyamino氨基色谱柱为固定相进行色谱分离。采用电喷雾离子源（ESI）负离子模式和多反应监测（MRM）模式进行质谱测定。采用基质匹配混合标准溶液系列制作工作曲线。结果表明：草铵膦、草甘膦、氨甲基膦酸工作曲线的线性范围分别为0.005~0.5 mg·L^-1，0.01~1.0 mg·L^-1，0.01~1.0 mg·L^-1；检出限（3S/N）分别为0.01，0.02，0.02 mg·kg^-1。对土壤样品进行3个浓度水平的加标回收试验，回收率为77.5%~92.0%，测定值的相对标准偏差（n=6）为5.9%~9.0%。

A method of UHPLC-triple quadrupole mass spectrometry after purification with solid phase extraction was established for determination of glufosinate, glyphosate and its metabolite aminomethylphosphonic acid in soil. Soil sample was mixed with water and dichloromethane, and homogenized at high speed for 1 min. After centrifugation, 3 mL of the supernatant was passed through Oasis HLB solid phase extraction cartridge, and the last 1 mL of eluent was collected, and filtered by 0.22 μm filtering membrane. The contents of glufosinate, glyphosate and its metabolite aminomethylphosphonic acid in the filtrate were determined by UHPLC-triple quadrupole mass spectrometry. In chromatographic analysis, a mixed solution composed of 5 mmol·L^-1 ammonium acetate (adjusting pH to 12 with ammonia) and acetonitrile with various volume ratios was used as the mobile phase for gradient elution, and the Dikma Polyamino amino chromatograhpic column was used as the stationary phase for chromatographic separation. ESI with negative ion mode and MRM mode were used for determination by mass spectrometry. The working curves were made with the matrix-matched mixed standard solution series. The results showed that the linearity ranges of the working curves of glufosinate, glyphosate and aminomethylphosphonic acid were 0.005-0.5 mg·L^-1, 0.01-1.0 mg·L^-1, 0.01-1.0 mg·L^-1, with their detection limits (3S/N) of 0.01, 0.02, 0.02 mg·kg^-1, respectively. The spiked recovery was made on the soil samples at 3 concentration levels, giving recoveries in the range of 77.5%-92.0%, and RSDs (n=6) of determined values were ranged from 5.9% to 9.0%.