Abstract
Traditionally, techniques used for the extraction of organic compounds from drinking and
waste water samples employed in EPA and Standard Methods are based either on
liquid/liquid extraction or liquid/solid extraction employing solid phase extraction (SPE)
disks or cartridges. Liquid/liquid extraction is the less desirable of the two because it
involves considerable time, labor, and expense. SPE reduces solvent consumption, but still
requires sample concentration, and is impractical when large quantities of particulates are
present in a sample.
This study investigates Immobilized Liquid Extraction (ILE) as an alternative technique
for preparing aqueous environmental samples for analysis by gas or liquid
chromatography. ILE is a form of liquid/liquid extraction in which the “organic” phase is
immobilized on the surface of an ILE device. Though the ILE method may be applied to
a number of procedures involving the extraction of organic compounds from aqueous
matrices (drinking water, blood serum, wastewater, etc.), the scope of this study is strictly
environmental, specifically relating to EPA methods 508, 525, 8270 and 8082. The
effectiveness of the ILE method was evaluated in the extraction and subsequent analysis
of polychlorinated biphenyls (PCBs) and other semivolatiles from spiked water samples.
Method detection limits, reduced sample sizes and solvent usage, complex matrix effects,
and enhanceable selectivity are discussed.
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