衍生化气相色谱质谱联用法同时测定烟叶多种植物甾醇

Simultaneous Determination of Phytosterol in Tobacco by Gas Chromatograhy Mass Spectrometry with Derivative

以丙酮为提取剂、1%硫酸-乙醇(V∶V)溶液和2.0 m ol/L氢氧化钾-乙醇分别作水解剂和皂化剂,利用三甲基氯硅烷和六甲基二硅烷作为硅醚化衍生试剂,采用气相色谱质谱联用仪同时检测烤烟烟叶中的多种甾醇化合物。采用内标校准曲线法对胆甾醇、菜油甾醇、豆甾醇、β-谷甾醇进行准确定量分析;利用内标相对定量法对β-香树脂醇、豆甾-5,24(28)-双稀-3-β-醇、羊毛甾醇进行相对定量。分析结果表明:该方法的检测限为4.2—9.6ng/g,平均回收率达到80%以上,平均相对标准偏差(RSD)<5%,适合批量烟叶样品中甾醇的同时定量分析。

A method for simutaneous determination of phytosterol in tabocco was developed.The samples were extracted with acetone,then hydrolyzed in 1% sulfuric acid of etnanol soluton（V∶V）,and saponified in 2.0mol/L potassium hydroxide of alcohol solution,reacted with trimethylchlorosilane and hexamethyldisilazane,and analyzed by gas chromatograhy mass spectrometry.By the curve of internal standard,cholesterol,campesterol,stigmasterol and β-sitosterol were quantitatively determined,and relative quantitative analysis was used in β-amyrin,stigmasta-5,24（28）-dien-3β-ol and lanosterol.The results showed that,the detection limit was 4.2—9.6ng/g,the average recovery was above 80% and the average RSD was below 5%.The conclusion was that the method was suitable to quantitative analysis of phytosterols in batches of tabocco samples.