挥发性有机物同分异构体光电离-离子迁移谱检测研究

自行研制的紫外光电离-离子迁移谱装置,对碳链异构、官能团异构和官能团位置异构的11种同分异构体挥发性有机物进行了实验研究,结果表明,这些有机同分异构体能够在离子迁移谱中实现分离。得到了11种挥发性有机物离子的约化迁移率,对实验所研究的同分异构体而言,迁移率大小符合以下规律:直链<分支<环状,一级<二级<三级,对位<间位<邻位,醇类<酮类<芳香类。实验中用指数稀释法对11种样品进行了定量分析,利用该方法得到装置检测限达到ppb～ppm量级。其中对丙醛、叔丁醇、乙苯、乙醚等同分异构体的光电离离子迁移谱研究均为首次报道。

Photoionization ion mobility spectrometry (UV-IMS) for the isomeric volatile organic compounds

The construction and performance study is reported for a newly developed ultraviolet photoionization ion mobility spectrometry (UV-IMS). In the present paper, an UV-IMS technique was firstly developed to detect eleven isomeric volatile organic compounds including the differences in the structure of carbon chain, the style of function group and the position of function group. Their reduced mobility values were determined and increased in this order: linears < branches < cycles, primary < secondary < tertiary, para- < meta- < ortho- and alcohols < acetones < aromas. The concentrations of analytes were obtained by means of exponential dilution method, and the experiments show that the limit of detection of the homemade UV-IMS was around ppb-ppm.