Solid-phase microextraction of polychlorinated biphenyls.

Y Yang; D J Miller; S B Hawthorne

doi:10.1016/s0021-9673(97)01115-1

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Solid-phase microextraction of polychlorinated biphenyls.

Y Yang·D J Miller·S B Hawthorne

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Abstract

The extraction and analysis of 21 polychlorinated biphenyls (PCBs) ranging from di- to decachlorobiphenyls in ocean, wetland and leachate water samples were achieved using solid-phase microextraction (SPME) with a 100-micron poly(di-methylsiloxane) (PDMS) fiber and gas chromatography-electron-capture detection (GC-ECD). Severe carryover between samples (e.g., 20%) occurs on both stir bars and the SPME fibers demonstrating that it is important to use a new stir bar for each sample, as well as to perform SPME-GC blanks between samples to avoid quantitative errors. The equilibrium partitioning coefficients of individual PCB congeners between PDMS and water were found to be surprisingly different compared to their octanol-water partitioning coefficient (Kow), demonstrating that Kow cannot be used to estimate the partitioning behavior of PCBs in the SPME process. Using a 15-min SPME extraction, SPME analysis with GC-ECD was linear (r2 > or = 0.97) from approximately 5 pg/ml to the solubility limit of each congener. Concentrations in water samples obtained by 15-min SPME extractions compared favorably with those obtained by toluene extractions, demonstrating that SPME combined with GC is a useful technique for the rapid determination of PCBs in water samples.

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Absorption Chromatography, Gas Dimethylpolysiloxanes Environmental Pollutants Linear Models Osmolar Concentration Polychlorinated Biphenyls Sensitivity and Specificity Silicones Wetting Agents Comparative Study Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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Y Yang, D J Miller, S B Hawthorne. 1998-03-27. Solid-phase microextraction of polychlorinated biphenyls.. https://doi.org/10.1016/s0021-9673(97)01115-1

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