高分辨GC-QTOF MS法分析烟草中的醛酮类香味成分

Aldehyde and ketone aroma components in tobacco analyzed by gas chromatography-quadrupole time-of-flight high-resolution mass spectrometry

基于气相色谱-四极杆飞行时间质谱(GC-QTOF MS),针对烟草及烟用添加剂中127种重要的醛酮类香味成分,建立了包含一级高分辨质谱图、保留指数和精确相对分子质量的数据库。优化了GC-QTOF MS分析条件,建立了127种化合物的准确定量分析方法,并对构建的方法进行系统表征。采用该方法分析了国内15个不同品牌卷烟样品。结果表明:①GC-QTOF MS采集的数据的精确质量误差均小于2 mDa,与传统GC-MS相比,采用数据库进行定性分析的结果更准确。②质量提取窗口为5 mDa时,可去除干扰离子,提高灵敏度。③127种醛酮类化合物标准曲线线性关系良好(r2>0.99);其中95种化合物的定量限(LOQs)在6~100μg/kg之间;3个添加水平下,平均回收率在61.8%~132.6%之间;115种化合物日间精密度(n=6)小于10%。④该方法适合各类卷烟烟丝样品中醛酮类香味成分的分析,在15个品牌卷烟样品中共检测到63种醛酮类香味成分,包括22种醛和41种酮。

Based on gas chromatography-quadrupole time-of-flight mass spectrometry(GC-QTOF MS),a database for 127 important aldehyde and ketone aroma components in tobacco and tobacco additives was established.The database collected the high resolution mass spectra,retention indexes and exact relative molecular masses for all the above compounds.The accurate quantitative analysis for the 127 compounds was developed by optimizing GC-QTOF MS conditions,and the developed method was characterized systematically.The samples of 15 domestic cigarette brands were analyzed using this method.The results showed that:1)The accurate mass errors of the data collected by GC-QTOF MS were all less than 2 mDa.Compared with traditional GC-MS method,the qualitative results were more accurate using the database.2)When mass extraction window was 5 mDa,the sensitivity could be improved by removing interfering ions.3)The developed method presented good linear relationships(r2>0.99)for the 127 aldehydes and ketones.The limits of quantitation(LOQs)of 95 compounds were in the range of 6-100μg/kg,and the average recoveries for all the targets were in the range of 61.8%-132.6%at three spiked levels.The inter-day precisions(n=6)of 115 compounds were less than 10%.4)This method was suitable for analyzing the aldehyde and ketone aroma components in cut tobacco of cigarettes.In total,63 aroma components,including 22 aldehydes and 41 ketones,were detected in the tested samples of the 15 cigarette brands.