用二氯甲烷提取样品中残留的10种有机膦农药(OPhP′s),所得萃取液用无水硫酸钠脱水后,在35 ℃和0.006 MPa的条件下经旋转蒸发至干,用二氯甲烷2.00 mL溶解残渣,此溶液毋需净化直接进样用气相色谱法进行测定.测定中采用DB-1701、RTX-5双毛细管色谱柱和双火焰光度检测器,10种农药的检出限(3S/N)在3~10 μg·L-1之间.用标准加入法在3个浓度水平上对方法的回收率及精密度作了试验,求得其回收率在83.3%~112.6%之间,相对标准偏差(n=8)在3.4%~6.9%之间.

Ten residual organophosphorus pesticides (OPhP′s) in strong tea were extracted from the sample with dichloromethane.The extract was dehydrated with anhydrous Na2SO4 and concentrated to 2.00 mL by rotary evaporation under the condition of 35 ℃ and 0.006 MPa.The sample solution was used for direct GC determination without purification,and binary capillary chromatographic columns of DB-1701 and RTX-5 and binary FPD detectors were adopted.Detection limits (3S/N) of the method for the 10 OPhP′s found were in the range of 3-10 μg·L-1.Tests for recovery and precision were made by standard addition method at 3 concentration levels,giving values of recovery and RSD′s (n=8) in the ranges of 83.3%-112.6% and 3.4%-6.9% respectively.