固相萃取GC-ECD法同时测定5种中药材中26种农药残留量

摘要

AIM: To develop an analytical method for the simultaneous determination of 26 pesticide residues including 21 organochlorines and 5 pyrethroids in 5 crude Chinese medicinal materials by gas chromatography-electron capture detector (GC-ECD) method. METHODS: Florisil solid-phase extraction (SPE) was used for the clean-up of samples and GC-ECD for the determination. The separation of the target pesticides was carried out on HP-5 quartz capillary column in an optimized oven program with nitrogen as a carrier at a constant flow of 1.0 mL·min-1and the injection inlet valve was set at 260 ～C and ECD at 330 ℃. RESULTS: The florisil solid-phase extraction was effective for the clean-up of the samples. For 26 pesticides, LODs and LOQs of the developed method were 0.386-2.500 ng·g-1 and 0.879-6.250 ng·g-1, respectively, and the average recoveries were found to be 69.61％-112.80％ (RSD = 2.43％-15.18％, n = 9). CONCLUSION: The developed method could be used to simultaneously determine the 26 pesticide residues in 5 Chinese medicinal materials, and it could also be potential in the determination of other similar Chinese medicinal materi-als.%目的:采用GC-ECD法建立5种药材中包括21种有机氯和5种拟除虫菊酯类在内的26种农药残留量的同时测定方法.方法:采用弗罗里硅土固相萃取净化样品,GC-ECD测定,HP-5弹性石英毛细管柱程序升温分离,载气为高纯N2,柱流量1.0mL·min-1,恒流方式控制气流,进样口温度260 ℃,ECD温度3300℃.结果:弗罗里硅土固相萃取能有效净化药材样品中杂质,26种农药检测限为0386-2.500 ng·g-1,定量限为0.879～6.250 ng·g-1,平均回收率为69.61%～112.80%(RSD=2.43%～15.18%,n=9).结论:所建立的方法能同时测定5种药材中26种农药残留量,可被参照应用于其它类似药材中的农药残留量检测.