Abstract:
Separation and isolation of organic analytes from environmental matrices such as soils,
water, plant, or animal tissue has traditionally involved the use of liquid solvent extractions.
Solvent-based extraction methods are often time-consuming, difficult to automate, and use
expensive solvents that generate hazardous waste and working conditions. The need for a rapid,
reproducible, inexpensive, environmentally-friendly, and non-destructive technique for sample
monitoring and quantitation have promoted the development of newer extraction techniques.
Conventional techniques for headspace analysis such as purge and trap have been developed to
limit solvent use and increase automation, however this method still requires some use of solvents
and sample manipulation.
Solid-phase microextraction (SPME) is a rapid, relatively inexpensive, and solvent-frce
extraction technique. The apparatus consists of a fused silica fiber, coated with a highly
absorbent organic phase, attached to a microsyringe for handling convenience (Figure 1). The
extraction procedure involves the exposure of the fiber directly into an aqueous sample or to a
sample's headspace. Upon equilibrium between the fiber coating and the sample, the fiber is
introduced to the heated inlet of the GC, where the analytes are completely desorbed from the
fiber coating'.