Li K, Santilli A, Goldthorp M, Whiticar S, Lambert P, Fingas M
Emergencies Science Division, Environment Canada, Environmental Technology Centre, River Road, Ottawa, Ont., Canada K1A OH3.
J Hazard Mater. 2001 May 7;83(1-2):83-91. doi: 10.1016/s0304-3894(00)00329-0.
Solid phase micro extraction (SPME) is a fast, solvent-less alternative to conventional charcoal tube sampling/carbon disulfide extraction for volatile organic compounds (VOC). In this work, SPME was compared to the active sampling technique in a typical lab atmosphere. Two different types of fibre coatings were evaluated for solvent vapour at ambient concentration. A general purpose 100 microm film polydimethylsiloxane (PDMS) fibre was found to be unsuitable for VOC work, despite the thick coating. The mixed-phase carboxen/PDMS fibre was found to be suitable. Sensitivity of the SPME was far greater than charcoal sorbent tube method. Calibration studies using typical solvent such as dichloromethane (DCM), benzene (B) and toluene (T) showed an optimal exposure time of 5 min, with a repeatability of less than 20% for a broad spectrum of organic vapour. Minimum detectable amount for DCM is in the range of 0.01 microg/l (0.003 ppmv). Variation among different fibres was generally within 30% at a vapour concentration of 1 microg DCM/l, which was more than adequate for field monitoring purpose. Adsorption characteristics and calibration procedures were studied. An actual application of SPME was carried out to measure background level of solvent vapour at a bench where DCM was used extensively. Agreement between the SPME and the charcoal sampling method was generally within a factor of two. No DCM concentration was found to be above the regulatory limit of 50 ppmv.
固相微萃取（SPME）是一种快速、无溶剂的方法，可替代传统的用于挥发性有机化合物（VOC）的活性炭管采样/二硫化碳萃取方法。在这项工作中，在典型的实验室环境中，将SPME与主动采样技术进行了比较。评估了两种不同类型的纤维涂层对环境浓度下溶剂蒸气的吸附情况。发现一种通用的100微米膜厚的聚二甲基硅氧烷（PDMS）纤维不适用于VOC分析，尽管其涂层较厚。发现混合相的碳分子筛/PDMS纤维是合适的。SPME的灵敏度远高于活性炭吸附管法。使用二氯甲烷（DCM）、苯（B）和甲苯（T）等典型溶剂进行的校准研究表明，最佳暴露时间为5分钟，对于广泛的有机蒸气，重复性小于20%。DCM的最低检测量在0.01微克/升（0.003 ppmv）范围内。在1微克DCM/升的蒸气浓度下，不同纤维之间的差异一般在30%以内，这对于现场监测目的来说已经足够。研究了吸附特性和校准程序。进行了SPME的实际应用，以测量一个广泛使用DCM的实验台上溶剂蒸气的背景水平。SPME和活性炭采样方法之间的一致性一般在两倍以内。未发现DCM浓度高于50 ppmv的监管限值。
