固相微萃取法同时分析源水中54种挥发性有机物

建立了同时测定饮用水源水中54种挥发性有机物的前处理方法———顶空固相微萃取法。用65μm聚二甲基硅氧烷二乙烯基苯(PDMS-DVB)固相微萃取柱顶空萃取水样中的挥发性有机物,萃取物用气相色谱/质谱联用法(GC-MS)分析,采用质谱(MS)检测器的选择离子监测模式(SIM)和内标法进行定量分析。试验优化了顶空固相微萃取条件,如萃取柱涂层、盐度、萃取温度和萃取时间等。采用优化后的条件获得的方法检出限为0.01～0.37μg/L,在所测浓度范围内校准曲线的相关系数良好(除三氯甲烷和四氯化碳外均大于0.991),对0.60μg/L标准水样测得结果的RSD均小于15%;实际饮用水源水样加标回收率均值和RSD分别为73.1%～130%和1.4%～19%(n=6)。该方法适用于饮用水源水中挥发性有机物的监测分析。

Simultaneous Determination of 54 Volatile Organic Compounds in Drinking Source Water Using Head-space Solid-phase Microextraction

Head-space solid-phase microextraction(HS-SPME) method for simultaneous determination of 54 volatile organic compounds(VOCs) in drinking source water was established.VOCs in water were extracted by 65 μm polydimethylsiloxane-divinylbenzene(PDMS-DVB) solid-phase micro-extraction column,and analyzed by gas chromatography and mass spectrometry(GC-MS) with selective ion monitoring(SIM) mode and internal standard quantitative method.Under the optimized conditions,such as SPME coatings,NaCl concentration,extraction temperature and extraction time,the correlation coefficient and the detection limit obtained were above 0.991(except for chloroform and carbon tetrachloride) and 0.01 to 0.37 μg/L respectively.RSDs of spiked blank samples at 0.60 μg/L were all less than 15%.The average recoveries and RSDs of spiked drinking source water samples were 73.1% to 130% and 1.4% to 19%(n=6) respectively.The method is suitable for the determination of VOCs in drinking source water sample.