Abstract: A gas chromatography system of the type incorporating a thermal focusing chamber for introducing a sample into a column for separation and analysis. The system of the present invention provides benefits in terms of reducing memory effect of one analysis being influenced by prior experiments, a reduction in system dead volume which leads to broadening of peaks produced on the chromatogram and artifacts caused by sample decomposition. These advantages are achieved principally through a novel fluid circuit in which the sample is trapped onto the column by trapping it at the end of the thermal focusing chamber closest to the column. This feature has the effect of eliminating the necessity of the sample residing in the heated focusing chamber for a period giving rise to sample decomposition. This system further avoids the necessity of passing the inlet flow through mechanical valves which also contributes to memory effect.

Abstract: A gas chromatography system which incorporates a simplified sample injection system in which replaces conventional mechanical injection systems with one based strictly upon thermal trapping of a continuously supplied carrier gas and sample stream. The carrier gas and sample stream pass continuously through the device which incorporates a thermal focusing chamber which communicates with the inlet end of a gas chromatography separation column. By causing the focusing chamber temperature of a sample tube passing through the focusing chamber to be dropped, incoming components comprising the sample stream are condensed and trapped. Injection into the column occurs rapidly heating the sample in the thermal focusing chamber causing a narrow sample plug to be introduced into the column.