目的建立饮用水中灭草松和2,4-滴的固相萃取高效液相色谱串联质谱测定方法。方法样品经C18固相萃取柱富集浓缩,利用C18色谱柱分离待测物,以甲醇和0.2%甲酸水溶液为流动相等度洗脱,负离子模式下质谱多反应监测(MRM)模式检测,外标法定量。结果灭草松和2,4-滴分别在0.122~298和0.612~1 488 ng/L的范围内线性关系良好,相关系数均大于0.999 0,检出限分别为0.078和0.235 ng/L,定量下限分别为0.261和0.782 ng/L。该方法灭草松的平均回收率为88.8%~103%,RSD<9.1%,2,4-滴的平均回收率为92.3%~93.1%,RSD<4.1%。结论该方法灵敏度和精密度均较高,回收率和重复性良好,适用于饮用水中灭草松和2,4-滴的测定。 Objective To establish a method for the determination of imazapyr and 2,4-D in tap water by high performance liquid chromatography-tandem mass spectrometry. Methods The sample was concentrated by C18 solid phase extraction column, the C18 column was used to separate the analytes. The mobile phase consisted of methanol and 0.2% formic acid eluted with equal mobility. The negative ion mode was detected by MRM. Legal quantity. Results Both imazapyr and 2,4-D had a good linear relationship in the range of 0.122-2988 and 0.612-1488 ng / L, the correlation coefficients were all greater than 0.999 0 with the detection limits of 0.078 and 0.235 ng / L, respectively The lower limit was 0.261 and 0.782 ng / L, respectively. The average recoveries of this method were 88.8% ~ 103%, RSD <9.1%. The average recoveries of 2,4-D were 92.3% ~ 93.1% with RSD <4.1%. Conclusion The method has high sensitivity and precision, good recovery and repeatability, and is suitable for the determination of MCP and 2,4-D in drinking water.