自动索氏-固相萃取-GC/MS测定土壤中多环芳烃方法的建立

Determination of Polycyclic Aromatic Hydrocarbons in Soil by Gas Chromatography/ Mass Spectrometry Associated with Automated Soxhlet Extraction and Solid-phase Extraction

为获得一种较为快捷、方便、准确的土壤多环芳烃分析方法,探讨了使用自动索氏-固相萃取-GC/MS的联用技术在土壤多环芳烃检测中的提取效果,并对比了前处理过程中使用分析纯溶剂与色谱纯溶剂对结果的影响,对固相萃取方法和GC/MS条件进行了优化。结果说明分析纯溶剂不适合作为萃取溶剂,选用硅胶小柱并使用正己烷/二氯甲烷(1∶1)作为淋洗溶剂时效果最好,MS离子源温度在300℃以上时可以大幅度的提高对高环多环芳烃的检测限。MS检测限在0.49μg/kg到2.53μg/kg之间,方法回收率除了萘为63.8%以外均在86.4%～119.1%之间。该方法比传统方法更为快捷,方便,更适合大量土壤样品的多环芳烃检测。

To obtained a quick, convenient and accurate method to analyze Polycyclic Aromatic Hydrocarbons （PAHs） in soil, the extraction effect of Gas Chromatography/Mass Spectrometry （GC/MS） associated with automated soxhlet extraction and solid-phase extraction on examination of PAHs in soil was discussed; to compared the effects of analytical pure solvent and chromatographic pure solvent used in treatment process, the method of solid-phase extraction and the conditions of GC/MS had been optimized. The results showed that analytical pure solvent was unsuitable for exaction solvent; by using silica-gel cartridges mixed with leaching solvent （n-hexane/dichloromethane =1：1）, the effect of extraction was the best; when the temperature of MS ion sources was above 300℃, the detection limit of PAHs could improve obviously. The detection limit of MS was between 0.49 μg/kg to 2.53 μg/kg, and the recovery rate was between 86.4% to 119.1% except Nap was 63.8%. These reasons were indicated that this method was more quick, convenient and accurate than traditional methods, more suit for the determination of PAHs in mass soil samples.