固相萃取-GC/MS法测定食品级润滑油中的多环芳烃

Determination of Polycyclic Aromatic Hydrocarbons in Food-grade Lubricating Oils by Solid Phase Extraction-Gas Chromatography-Mass Spectrometry

建立了经固相萃取柱净化、气相色谱-质谱联用法（GC/MS）同时测定食品级润滑油中16种美国EPA优控多环芳烃（PAHs）的分析方法。食品级润滑油样品用环己烷溶解后,用经环己烷饱和的二甲基亚砜萃取、环己烷和氯化钠溶液反萃取、固相萃取柱净化前处理,采用GC/MS选择离子扫描模式进行定性定量分析;优化了前处理和仪器分析条件。采用内标法定量,食品级润滑油中16种PAHs的添加回收率在80.92%～109.48%之间,相对标准偏差为2.44%～4.87%,样品中PAHs检出限为0.01～0.05 mg/kg、定量限为0.03～0.16 mg/kg,方法的线性范围为0.005～10 mg/L,相关系数均大于0.998 8。

The method of solid phase extraction-gas chromatography-mass spectrometry（GC/MS） for measuring 16 EPA priority polycyclic aromatic hydrocarbons（PAHs） contained in food-grade lubricating oils was established. The sample was solved in cyclohexane and extracted by cyclohexane saturated dimethyl sulphoxide, and then back extracted by cyclohexane, followed purified by solid phase extraction column. The solution obtained was analyzed qualitatively and quantitatively by GC/MS and the pretreating methods and GC/MS condition were optimized. The average recoveries of PAHs were 80.92%～109.48%, and the relative standard deviations were between 2.44%～4.87%. The limit of detection（LOD） of PAHs in food-grade lubricating oils was 0.01～0.05 mg/kg, and the limit of quantitation（LOQ） was 0.03～0.16 mg/kg. The linearity range was between 0.005～10 mg/L, with all of the correlation coefficients higher than 0.998 8.