真空辅助顶空固相微萃取/气相色谱-质谱法测定地下水中9种多氯联苯OA

To compensate the absence of some polychlorinated biphenyls(PCBs)items in water qual-ity monitoring,a new environmentally friendly,efficient and sensitive analytical method for 9 PCBs in groundwater was established by using vacuum-assisted headspace solid-phase microextraction tech-nology(Vac-HS-SPME)for enrichment and gas chromatography-mass spectrometry(GC-MS)for de-tection.Experimental conditions including extraction fiber type,extraction temperature,extraction time,and stirring speed were optimized as 65 µm PDMS/DVB extraction fiber at 70℃with a stirring speed of 500 r/min for a duration of 40 min.9 target PCBs exhibited excellent linearities within the range of 0.02-2.0 µg/L with correlation coefficients(r)between 0.998 1-0.999 4.Method detec-tion limits varied from 0.002 to 0.016 µg/L.The spiked recoveries of the 9 PCBs ranged from 78.9%to 115%,with relative standard deviations(n=6)between 2.8%-12%.In comparison to traditional headspace solid-phase microextraction(HS-SPME)techniques,Vac-HS-SPME offers enhanced sensitivity and extraction efficiency-particularly for PCBs with higher chlorination levels.This meth-od is simple to operate,environmentally friendly and highly sensitive and has been successfully ap-plied to the determination of actual groundwater samples,providing a new technical means for the qualitative and quantitative analysis of PCBs in environmental water samples.