Solid-phase microextraction of polychlorinated biphenyls.
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.
Yang
Y
Y
Energy and Environmental Research Center, University of North Dakota, Grand Forks 58202, USA.
Miller
D J
DJ
Hawthorne
S B
SB
D000042:Absorption; D002849:Chromatography, Gas / Q000379:methods*; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D004785:Environmental Pollutants / Q000032:analysis*; D016014:Linear Models; D009994:Osmolar Concentration; D011078:Polychlorinated Biphenyls / Q000737:chemistry*; D012680:Sensitivity and Specificity; D012828:Silicones / Q000737:chemistry*; D014906:Wetting Agents / Q000737:chemistry*
D004129:Dimethylpolysiloxanes; D004785:Environmental Pollutants; D012828:Silicones; D014906:Wetting Agents; C013830:baysilon; D011078:Polychlorinated Biphenyls