分散液-液微萃取-气相色谱-质谱法同时测定中毒样品中有毒生物碱和鼠药

Simultaneous Determination of Toxic Alkaloids and Rat Poisons in Toxic Samples by Dispersive Liquid-liquid Micro-extraction Combined with Gas Chromatography-Mass Spectrometry

建立了分散液-液微萃取（ Dispersive liquid-liquid micro-extraction, DLLME）与气相色谱-质谱（ GC-MS）联用同时测定中毒样品中3种鼠药（毒鼠强、溴鼠灵、溴敌隆）和5种有毒生物碱（莨菪碱、东莨菪碱碱、钩吻碱、士的宁、马钱子碱）的方法。100μL萃取剂氯仿与600μL分散剂甲醇混合后,迅速注入样品,萃取过程在乳化体系中完成；以8000 r/min离心5 min,使两相分层,取下层有机相进行GC-MS分析。考察了萃取剂、分散剂的种类和体积、萃取时间、pH值及盐浓度对萃取效率的影响。在优化条件下,各目标物在水样、尿样、黄酒样的检出限为0.003~1.0μg/L,在米饭样品检出限为0.002~0.2μg/kg；各目标物低、中、高加标回收率为81.0%~110%,精密度均小于7%。本方法灵敏度高,快捷高效,适用于中毒样品中有毒生物碱和鼠药的同时测定。

A novel method for simultaneous determination of 3 rat poisons （ tetramine, bromadiolone, brodifacoum） and 5 toxic alkaloids （ hyoscyamine, scopolamine, gelsemine, strychnine, brucine ） in toxic samples by dispersive liquid-liquid micro-extraction （ DLLME ） coupled with gas chromatography-mass spectrometry was established. A mixture extractant containing 100 μL trichloromethane and 600 μL methanol was injected into the prepared sample to form an emulsion and the extraction process was accomplished. After centrifuged at 8000 r/min for 5 min, the settled drop of trichloromethane solvent was transferred to a conical insert within a GC autosampler vessel, and analyzed by GC-MS. Factors affecting extraction efficiency such as the type and volume of extractant, dispersive agent, extraction time, pH value and salt concentration of extraction system were studied. The limits of detection（LODs） were from 0. 003 to 1 μg/L in water sample, urine sample and rice wine sample. LODs were from 0. 002 to 0. 2 μg/kg in rice sample. The recoveries of toxic samples were in the range of 81. 0%-110%. The relative standard deviations（ RSDs） were lower than 7%. The proposed method was sensitive, effective, and suitable for the simultaneous determination of toxic alkaloids and rat poisons in food poisoning sample.