【摘要】 建立了以凝胶渗透色谱(GPC)和固相萃取(SPE)净化、气相色谱-质谱(GC-MS)法同时测定紫皮石斛中10种有机磷农药残留的方法。样品用乙腈超声提取,提取液经GPC去除类脂杂质和大分子物质,后经Envi-Carb/NH2固相萃取柱净化,选择离子(SIM)监测模式检测,外标法定量。在26min内10种农药得到很好的分离,农药残留量在0.02~0.5μg/mL,方法的线性良好,相关系数为0.997 3~0.999 9,农药加标浓度为0.05mg/kg和0.2mg/kg时,加标回收率在70.4%~115.8%,相对标准偏差在2.8%~9.6%,满足国家标准要求,检出限为0.005 2~0.011mg/kg。方法简便、快速、灵敏、准确,能够运用于石斛中多组分有机磷农药残留的定性和定量分析。更多还原

【Abstract】 A novel method has been developed for simultaneous determination of ten organophosphorous pesticide residues in Dendrobium Devoninum Paxt based on automatic gel permeation chromatography(GPC)coupled with solid phase extraction(SPE)-gas chromatography-mass spectrometry(GC-MS).The sample was extracted with acetonitrile by ultrasonic extraction.The automatic gel permeation chromatography was used to remove the macromolecule interference material and fat,and then the pigment in the extraction solution was purified by Envi-Carb/NH2 solid phase extraction.The qualitative analysis was performed by using mass spectrometric detection in the selected ion-monitoring(SIM)mode under the optimal chromatographic conditions.The external standard method was adopted for quantitative analysis.Ten organophosphorous pesticides were separated from each other within 26 minutes,A good linearity was in the range of 0.02~0.5μg/mL with correlation coefficients of 0.997 3~0.999 9.The recoveries ofpesticides at spiked levels of 0.05 and 0.2mg/kg were 70.4%~115.8%.The detection limits were 0.0052~0.011mg/kg with therelative standard deviations(RSDs)of less than 16%.The method is rapid,accurate and sensitive,and can meet the demand of determining organophosphorous pesticide residues in Dendrobium.更多还原