中空纤维液相微萃取-气相色谱法测定白芍中20种农药残留___

目的：建立白芍中20种有机氯和拟除虫菊酯类农药的检测方法。方法：采用中空纤维液相微萃取-气相色谱法，色谱柱为HP-5石英毛细管柱(30 m×0.25 mm×0.25 μm) 柱温(程序升温)：150 ℃为起始温度，以5 ℃•min-1的升温速率升至250 ℃，保持1 min，再以2 ℃•min-1的升温速率升至270 ℃，保持5 min 进样口温度：230 ℃ ECD检测器温度：280 ℃ 载气为氮气，测定白芍中20种有机氯和拟除虫菊酯类农药残留量。结果：有机氯和拟除虫菊酯类农药分别在0.4～40 μg• L-1和0.8～80 μg• L-1 范围内呈良好线性关系，r值范围为0.9970～0.9998。平均回收率(n=9)为82.5%～109.2%(RSD<10%)。结论：该方法操作简便快速，灵敏度高，准确度好，可作为中药材中有机氯和拟除虫菊酯类农药残留的测定方法。

Objective:To establish a method for detecting the 20 organochlorine and pyrethroid pesticide residues in Radix paeoniae Alba.Methods:Hollow fiber-based liquid phase microextraction GC with HP-5 column ( 30 m×0.25 mm×0.25 μm )was used to determine 20 organochlorine and pyrethroid pesticide residues in Radix paeoniae Alba.;The column temperature programming was initial temperature 150 ℃,with the increasing rate of 5 ℃• min-1 to 250 ℃(hold 1 min),then with the increasing rate of 2 ℃• min-1 to 270 ℃(hold 5 min);The injector temperature was 230 ℃ and ECD detector temperature was 280 ℃;The carrier gas was nitrogen.Results:The calibration curves were linear over the concentraction range of 0.4-40 μg• L-1 for organochlorine pesticides and 0.8-80 μg• L-1 for pyrethroid pesticides ( r was in the range of 0.9970-0.9998 ).The average recoveries ( n=9 ) of 20 pesticides were 82.5%-109.2% (RSD < 10%).Conclusion:The method is simple,accurate and sensitive.It can be used for the determination of organochlorine and pyrethroid pesticide residues in Chinese herbal medicines.