固相微萃取-气相色谱-质谱联机测定饮用水中的嗅、味化合物

Determination of odour-producing chemicals in drinking water by solid-phase microextraction and chromatography-mass spectrometry

测定水样中的土味素(Geosmin)和2 -甲基异冰片(MIB)时,浓缩方法主要有闭环萃取分析和固相微萃取(SPME)分析。闭环萃取分析法检出限很低,但是费用高、操作复杂且费时较长,而美国SUPEL CO推出的SPME技术克服了传统的样品预处理技术的缺陷,它无需溶剂和复杂装置,能直接从液体或气体样品中采集挥发和非挥发性的化合物,可以直接在GC、GC/MS和HPLC上分析。能与任何型号的气相或液相色谱连用,有手动和自动进样两种[1] 。本文应用SPME -GC -MS ,在优化了萃取头涂层种类、萃取时间、搅拌速度、离子强度、温度和溶液的pH值等条件的基础上,对水中的嗅、味化合物(土味素和2 -甲基异冰片)进行测定,结果令人满意。

When we detect geosmin and 2-methylisoborneol in water, the concentrating methods are closed-loop stripping analysis(CLSA)and solid-phase microextraction(SPME) mainly. The method of CLSA has a very low limit of detection, but it is expensive,complex,and need more time. The technique SPME produced by SUPELCO of american has overcomed the drawbacks of traditional pretreatment.It can directly pick up volatile or involatile compounds from liquid or gas without solvent and complex equipment.It can be connected with various kinds of GC、GC/MS and HPLC directly. There are two kinds of sample methods manually and automatically.In this article we optimize some factors: extracting fibre,extracting time,stirring rate,ion sensitivity,temperature and pH. The results of detecting geosmin and 2-methylisoborneol is good.