管内固相微萃取-气相色谱法联用在线测定水中有机物

Determination of organic substances in water by in-tube solid-phase microextra ction coupled with gas chromatography

将管内固相微萃取与气相色谱法结合,建立了水中痕量有机物的在线分析装置。采用毛细管气相色谱柱作为萃取柱,水样中的分析物在萃取柱中被萃取浓缩,溶剂解吸后的样品通过阀切换和柱内进样技术直接由载气携带进入气相色谱柱。采用OV 1萃取柱,对水样中的5种芳烃的富集倍数为34～85。

An on-line in-tube solid-phase microextraction (SPME) coupled with gas chroma tography (GC) for the enrichment and determination of trace organic substances i n water was established and evaluated. A wall-coated open tubular fused-s ilica capillary column (WCOT) coated with an appropriate stationary phase was us ed as an extraction column. Target substances in aqueous sample were directly ex tracted and concentrated to the capillary coating layer, then desorbed by solven t. The extracts were transferred to the GC column by carrier gas flow using valv e switching and in-column injection technique. Enrichment factors for five arom atic compounds in water were 34～85 times with OV-1 extraction column.