GC-MS结合保留指数对三甲基芳基类异戊二烯的定性

Qualitative Analysis of Trimethylaryl Isoprenoids Using GC-MS Combined with Retention Indices

2,3,4-和2,3,6-三甲基芳基类异戊二烯是地质体中典型的芳香生物标志化合物,具有明确的生源和环境意义。2个系列化合物具有极其相似的质谱特征,以至于难以对其准确判定。柴达木盆地盐湖相沉积体系检测出了丰富的2,3,4-和2,3,6-三甲基芳基类异戊二烯,两者虽展现出颇为相似的质谱分布特征,但其色谱保留时间存在明显差异。故利用质谱离子特征分析并结合其保留指数可对2,3,4-和2,3,6-三甲基芳基类异戊二烯进行准确定性。

The 2,3,6-and 2,3,4-trimethyl aryl isoprenoids were typical aromatic biomarkers in sedimentary systems,they had explicit origin and environmental significance.Isomers of the two series almost had identical mass spectra,resulting in difficulty for accurate judgment.Abundant 2,3,6-and 2,3,4-trimethyl aryl isoprenoids in the saline lacustrine systems were detected in the western Qaidam Basin,although they displayed a remarkably similar distribution in mass-chromatograms,but they had significant differences in chromatographic retention times.Therefore,2,3,6-and 2,3,4-trimethyl aryl isoprenoids can be accurately assigned in combination of mass spectra with GC retention indexes.