Application of programmed-temperature split/splitless injection to the trace analysis of aliphatic hydrocarbons by gas chromatography

The dependence of the programmed-temperature solvent split sampling techniq ue using a PSS (programmed-split/ splitless) injection mode on different va riables affecting the introduction of large sample volumes for a mixture of alkanes in capillary GC was evaluated. Apart from the studies found in the literature on different factors such as speed of injection, presence of ad sorbent in the liner, internal diameter of the liner, initial and final inj ector temperature, split flow-rate and initial split time, affecting the ch romatographic signal of different compounds, others were studied whose infl uence has not been considered until now. They include length of the microsy ringe needle, adsorbent distribution in the liner, injection volume on anal yte discrimination, speed of injector heating, time which the column stays at the initial temperature and time that the injector stays at the final te mperature. Once finalised, the study of the PSS injection mode was compared with the conventional mode of gas chromatography splitless injection, and found that the proposed method increases sensitivity in GC trace analysis. Finally, the application of both injection modes in the determination of al iphatic hydrocarbons was tested in an atmospheric particulate sample. (C) 2 001 Elsevier Science B.V. All rights reserved.