Key Laboratory of Nature Resource of the Changbai Mountain and Functional Molecular, Yanbian University, Ministry of Education, Park Road 977, Yanji City, Jilin Province 133002, China.
J Chromatogr A. 2011 Mar 25;1218(12):1549-55. doi: 10.1016/j.chroma.2011.01.018. Epub 2011 Jan 14.
Sample pretreatment before chromatographic analysis is the most time consuming and error prone part of analytical procedures, yet it is a key factor in the final success of the analysis. A quantitative and fast liquid phase microextraction technique termed as gas purge microsyringe extraction (GP-MSE) has been developed for simultaneous direct gas chromatography-mass spectrometry (GC-MS) analysis of volatile and semivolatile chemicals without cleanup process. Use of a gas flowing system, temperature control and a conventional microsyringe greatly increased the surface area of the liquid phase micro solvent, and led to quantitative recoveries of both volatile and semivolatile chemicals within short extraction time of only 2 min. Recoveries of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and alkylphenols (APs) determined were 85-107%, and reproducibility was between 2.8% and 8.5%. In particular, the technique shows high sensitivity for semivolatile chemicals which is difficult to achieve in other sample pretreatment techniques such as headspace-liquid phase microextraction. The variables affecting extraction efficiency such as gas flow rate, extraction time, extracting solvent type, temperature of sample and extracting solvent were investigated. Finally, the technique was evaluated to determine PAHs, APs and OCPs from plant and soil samples. The experimental results demonstrated that the technique is economic, sensitive to both volatile and semivolatile chemicals, is fast, simple to operate, and allows quantitative extraction. On-site monitoring of volatile and semivolatile chemicals is now possible using this technique due to the simplification and speed of sample treatment.
色谱分析前的样品预处理是分析过程中最耗时和最容易出错的部分，但它是分析最终成功的关键因素。本文开发了一种称为气体吹扫微量注射器萃取（GP-MSE）的定量快速液相微萃取技术，可用于挥发性和半挥发性化学物质的直接气相色谱-质谱（GC-MS）分析，无需进行清洗过程。使用气体流动系统、温度控制和常规微量注射器大大增加了液相微溶剂的表面积，并且在仅 2 分钟的短萃取时间内实现了挥发性和半挥发性化学物质的定量回收。多环芳烃（PAHs）、有机氯农药（OCPs）和烷基酚（APs）的回收率为 85-107%，重现性在 2.8%至 8.5%之间。特别是，该技术对半挥发性化学物质具有很高的灵敏度，这在其他样品预处理技术（如顶空-液相微萃取）中很难实现。研究了影响萃取效率的变量，如气流速度、萃取时间、萃取溶剂类型、样品和萃取溶剂的温度。最后，该技术用于测定植物和土壤样品中的 PAHs、APs 和 OCPs。实验结果表明，该技术经济实惠，对挥发性和半挥发性化学物质均具有较高的灵敏度，快速、简单、易于操作，并且允许进行定量萃取。由于样品处理的简化和速度，现在可以使用该技术进行挥发性和半挥发性化学物质的现场监测。
