Static headspace, solid-phase microextraction and headspace solid-phase microextraction for BTEX determination in aqueous samples by gas chromatography

Abstract

The determination of benzene, toluene, ethylbenzene and xylenes (BTEX) in aqueous samples by gas chromatography with flame ionization detection (GC–FID) with three sampling techniques, viz. static headspace (HS), solid-phase microextraction (SPME) and combined HS–SPME by using a polydimethylsiloxane fiber has been investigated. Experimental parameters optimisation of the BTEX determinations using the three techniques are given. At their optimum conditions of operation, detection limits, times required for analysis and precision observed for the three techniques used are established. A detailed comparison of the analytical performance characteristics of HS, SPME and HS–SPME as sampling techniques for final GC–FID determination of BTEX in waters is given. Although all three techniques turned out to be sufficiently accurate, offering detection limits on the ≤ng ml −1 range, the most sensitive, selective and least time consuming technique was HS–SPME, which seems to be particularly appropriate for routine analysis of BTEX in waters by GC.