气相色谱法测定熟地中有机氯类农药残留量

目的对熟地中 12种有机氯农药的毛细管气相色谱测定方法的研究。方法采用FDA方法提取、硫酸磺化后 ,采用不分流进样方式 ,用DB - 1弹性石英毛细管柱经柱程序升温技术分离 ,并用电子捕获检测器检测 ,外标法计算含量。结果高、中、低 3种浓度的平均回收率为 74 6 %～10 1 9% ,RSD为 0 8%～ 5 3% ;被测样品中均含有不同程度的农药残留。结论本方法可用于熟地中 12种有机氯农药残留量的测定

Determination of the organochorine pesticide residues in the Radix Rehmanniae preparata by the CGC-ECD

Objective To determine 12 organochlorine pesticide residues in the Radix Rehmanniae preparata by the capillary gas chromatography with the electron capture detector(CGC-ECD).Methods The samples were extracted by the FDA method.The capillary column was DB-1( 30 m × 0 25 mm × 0 25 μm );the injector temperature was 250 ℃;the detector temperature was 280 ℃;the column temperature program:the initial temperature was 150 ℃ ,rate of 15 ℃·min -1 to 180 ℃ (hold 1 min ),rate of 10 ℃·min -1 to 210 ℃ (hold 2 min ),rate of 15 ℃·min -1 to 240 ℃ (hold 10 min ).The pesticide residues were calculated by the external standard method.Results The recoveries and the RSD ranged from 74.6% to 101.9% and 0.8% to 5.3% respectively,at the three spiked mixed organochlorine pesticide levels.Conclusions The method is easy to operate and has good separation and repeatability.