猪肉中有机氯农药多组分的顶空固相微萃取-气相色谱-质谱检测技术初探

目的探讨建立顶空固相微萃取快速测定有机氯农药残留方法。方法以稳定性同位素13C6-六氯苯和13C10-灭蚁灵为内标,以顶空固相微萃取作为猪肉样品的前处理手段,采用气相色谱-质谱的选择离子模式(SIM)测定猪肉样品中18种有机氯农药组分。通过对萃取头类型、萃取时间、萃取温度、解析温度和时间、盐溶液的浓度等影响萃取效率的因素的研究,获得了优化的试验参数。结果在给定条件下,方法线性范围在1~100ng/kg范围内,混和标准溶液的加标回收率在90%~120%之间,相对标准偏差在3%~15%之间。结论本方法适合于猪肉样品中的有机氯农药多残留的快速检测,为农药残留的筛选提供了有效的监测手段。

Headspace Solid-phase Microextraction Combines with Gas Chromatography Mass Spectrometry for Determination of Organochlorine Pesticides in Pork Sample

Objective Headspace solid-phase microextraction (HS-SPME) was used as a clean-up and pre-concentration procedure for the simultaneous determination of organochlorine pesticides(OCPs)in pork samples. Method Two stable isotopic compounds, 13C labeled mirex and 13C labeled hexachlorobenzene, were used as internal standard. Gas chromatographic analysis with mass spectrometry (GC-MS) facilitates sensitive detection of the selected pesticides. Several parameters controlling SPME were studied and optimised: choice of SPME fiber, extraction temperature, extraction time, desorption time, desorption temperature and content of salt. Result Under optimal conditions, detection limits obtained were in the range of 1 to 100 ng/g depending on pesticide. Good recoveries (range from 90% to 120% in most cases) were achieved. Conclision The result showed that the HS-SPME/GC-MS method is suitable for the analysis of multi-residue OCPs in pork sample.