Solid phase microextraction/isothermal GC for rapid analysis of complex organic samples

Solid phase microextraction (SPME) was used as the sample introduction technique for high-speed isothermal GC. An injector dedicated for SPME fiber injection was designed and built. The injector was operated in two modes, continuously heated and flash heated. The latter mode proved to be better for high-speed separations. The injector was then used for sample introduction in separation of BTEX. When sampling directly from water with a fiber having a 56 μm thick poly(dimethylsiloxane) coating, the BTEX components were separated under isothermal conditions in ca. 18 s. A fiber with a thinner coating (15 μm) enabled the separation to be completed in ca. 12 s when sampling from headspace. In both cases the results were highly reproducible, as measured by the estimated values of the relative standard deviation.