水样中莠去津和呋喃丹通过C18固相萃取柱使之分离并富集。用氮气将固相萃取柱吹干后,用二氯甲烷淋洗使被测组分洗脱,所得洗脱液用氮气吹至尽干,用混合溶剂［甲醇与甲酸-水(0.1+99.9)溶液按40比60的比例混合］ 1 mL溶解残渣,所得溶液供超高效液相色谱-串联质谱法(UPLC-MS/MS)分析用。用Waters BEH C18色谱柱作分离柱,用不同比例的甲醇和甲酸-水(0.1+99.9)溶液的混合液作流动相进行梯度淋洗,使上述两种农药分离后进行串联质谱测定,所用质谱条件为电喷雾离子源,正离子扫描和多反应监测模式。两种农药质量浓度均在0.10~10.00 μg·L-1范围内与相应的峰面积值呈线性关系,检出限(3S/N)均为0.15 ng·L-1。在3个浓度水平上(0.10,0.50,5.00 μg·L-1)加入两种农药的标准溶液进行回收试验,测得其平均回收率在77.0%~102.2%之间,相对标准偏差(n=5)在2.9%~7.6%之间。

Atrazine and carbofuran in water sample were separated and enriched by passing through C18 SPE column. The SPE column was dried by N2-blowing and eluted with dichloromethane to desorb the analytes. The eluate was evaporated to dryness by N2-blowing and the residue was dissolved with 1 mL of the solvent mixture of methanol and dil. formic acid (0.1+99.9) mixed in the ratio of 40 to 60. The solution obtained was used for UPLC-MS/MS analysis. The waters BEH C18 chromatographic column and mobile phase of methanol and dil. formic acid (0.1+99.9) were used for separation by gradient elution. The determination by the MS/MS was performed under the conditions of electrospray ionization source, positive ion scanning and multireaction monitoring. Linear relationship between values of peak area and mass concentration of either of the pesticides was found in the same range of 0.10-10.00 μg·L-1, with same value of detection limits (3S/N) of 0.15 ng·L-1. Tests for recovery were performed by addition of the pesticide standards at 3 concentration levels (i.e. 0.10, 0.50 and 5.00 μg·L-1) for 5 parallel determinations each, results of average recovery found were in the range of 77.0%-102.2% with RSD′s (n=5) ranged from 2.9% to 7.6%.