提高水中痕量PAHs的SPE富集效率和降低背景干扰的考察

Method for Improving Recovery and Reducing Interferences in SPE Enrichment of Trace Amounts of PAHs in Water

摘要: 固相萃取(SPE)是目前广泛采用的富集水中痕量多环芳烃（PAHs）的前处理方法，具有回收率高、检测限低、不乳化等优点.在操作过程中，提高回收率和控制背景干扰是SPE能否达到测试分析要求的关键技术.从样品的准备、C18柱的活化、样品的抽滤萃取、C18柱的干燥和洗脱、洗脱液的浓缩和保存等方面讨论了SPE富集水中痕量PAHs的影响因素和提高PAHs回收率的方法，以及如何消除背景干扰，并进行了回收率的验证实验.在14个流沙湾海水样品的测试中，除萘-d8外其它4种替代物的回收率均在60%~120%，相对标准偏差RSD≤10%，达到水中PAHs分析测试的要求.

Abstract: Solid phase extraction （SPE） is one of the commonly used pretreatment methods for the concentration of trace amounts of PAHs in water. It has the advantages of high extraction recovery, low detection limit and nonemulsifiability. Improving the recovery and controlling the background interference are the key factors of the SPE method. The influencing factors and solutions for improving recovery and reducing interferences in SPE are discussed. 14 water samples of Liu Sha Bay were monitored by SPE/GC-MS in this study. The results showed that recoveries of 5 substitute compounds ,except for naphtalene-d8, were 60%~120% and relative standard deviations were lower than 10%. This method can be used to monitor the concentrations of PAHs in water.