顶空-固相微萃取/气相色谱-质谱联用法快速分析海水中13种苯系物

Fast Analysis of Benzene Series (BTEX) in Seawater by Headspace Solid Phase Microextraction Coupled with GC-MS

建立了同时测定海水中常见的13种痕量苯系物（BTEX）的顶空-固相微萃取/气相色谱-质谱联用（HS-SPME/GC-MS）检测方法.利用涂有100 μm Polydimethylsiloxane（PDMS）涂层的萃取头顶空萃取海水样品,GC-MS检测和外标定量法对目标物进行分析.实验对萃取纤维头的类型、萃取温度、萃取时间、解吸时间、样品体积等主要萃取条件进行了优化.在优化萃取条件下,13种苯系物的线性范围为0.16～ 32 μg/L,相关系数为0.9990～1.0000,检出限为0.006～0.043 μg/L.在3个加标水平（0.16、1.6、16 μg/L）下,海水样品中13种苯系物的回收率为80.0％～117％,相对标准偏差（RSD,n=6）为2.0％～5.6％.该方法前处理简便易行、灵敏度高,为海水中痕量苯系物的检测提供了一种简便、快捷、环保的测定方法.

A gas chromatography（GC）-mass spectrometric （MS） method coupled with headspace solid phase microextraction（HS-SPME/GC-MS） was established to analyze 13 benzene series（BTEX） in seawater.The seawater samples were extracted by 100 μm polydimethylsiloxane（PDMS） fiber,and determined by GC-MS under selective ion mass mode with the external standard method.Several factors affecting the extraction efficiencies were optimized,including type of fiber,extraction temperature,extraction time,desorption time and sample volume.Under the optimized conditions,the linear equations were obtained in the concentration range of 0.16-32 μg/L with correlation coefficient（r） of 0.999 0-1.000 0.The limits of detection（S/N =3） were in the ranges of 0.006-0.043 μg/L.The recoveries at three spiked levels of 0.16,1.6,16 μg/L ranged from 80.0％ to 117％ with relative standard deviations （RSD,n =6） of 2.0％-5.6％.The proposed method was simple,sensitive,rapid and green,and was suitable for the determination of 13 BTEX in seawater.