Potential and limitations of differently designed programmed-temperature injector liners for large volume sample introduction in capillary GC

Programmed temperature sample introduction is an attractive technique both for the introduction of large volumes of dilute samples in capillary gas chromatography and for LC‐GC interfacing. In this study a new type of liner containing a porous bed of sintered glass is introduced and evaluated. Solute recoveries achieved with this liner are compared with those obtained from liners packed with Tenax TA and Thermotrap TA. An open liner containing baffles and a small plug of silanized glass wool in its upper section was used as a reference. The maximum speed of sample introduction allowable using the new liner is ca one order of magnitude higher than for the standard liner. For similar liner operating conditions the trapping efficiency is substantially improved: at a liner temperature of −30°C components with a volatility lower than or equal to that of n‐tridecane are trapped quantitatively. Liners packed with trapping materials such as Tenax TA or Thermotrap TA also provide significantly improved trapping efficiencies, even when used at relatively high temperatures.