Rw. Current et Aj. Borgerding, Rapid extraction high-speed GC analysis of volatile organic compounds in aqueous samples, ANALYT CHEM, 71(16), 1999, pp. 3513-3518
An extraction system to remove volatile organic compounds (VOCs) from an aq
ueous matrix in a time frame that is compatible with high-speed gas chromat
ography (HSGC) has been developed and interfaced to a cryofocusing instrume
nt. Using this system, VOCs are quantitatively extracted in similar to 20 s
, with no residual signal present during subsequent analysis. This allows s
uccessive injections, as demonstrated by sequential extraction and separati
on of four aqueous samples in less than 31/2 min. Analysis time was minimiz
ed by designing the system to allow concurrent extraction and separation. T
he entire sample extract is introduced to the cryofocusing injector of the
HSGC, resulting in excellent sensitivity. Injection of only 100 mu L of an
aqueous mixture of VOCs in the low parts per billion range resulted in chro
matographic peaks with signal-to-noise ratios ranging from 6.5 to 41 depend
ing on analyte. Reproducibility of sequential analyses at this concentratio
n resulted in less than 5% relative standard deviation.