Sample introduction in gas chromatography using a coiled wire filament

Recent applications in analytical thermochemolysis

“…The end of the wire coil is dipped in a liquid sample, then the wire is introduced into the hot injection port of GC. It was reported that the extraction efficiency was good compared to a commercially available solid phase microextraction (SPME) [39].…”

An Injection Cannula that Enhances the Versatility of Split–Splitless Inlets

“…We have established the feasibility of on-column injections by inserting a fine glass tube through the cannula and into a 250 lm column, with a Uniliner (Restek, Bellefonte, PA) inlet liner to steer the tip of the needle into the column. The cannula replicates the function of earlier on-column needle guides [1,14], but it is more versatile and is simpler in construction and operation, and does not need the GC inlet to be replaced.…”

“…This limits the diameter of SPME and inneedle traps, which restricts the volume of SPME absorbents to less than a microliter and the mass of adsorbents to a few milligrams, and in turn limits breakthrough volumes and limits of detection and quantitation [2,3]. Making these devices larger makes them more robust, and improves detection limits [2,[4][5][6][7], but then they cannot be inserted through standard septa. Fused-silica needles and transfer lines are free of the catalytic and adsorptive activity of stainless steel [1,8], but have very sharp edges that core septa.…”

“…Making these devices larger makes them more robust, and improves detection limits [2,[4][5][6][7], but then they cannot be inserted through standard septa. Fused-silica needles and transfer lines are free of the catalytic and adsorptive activity of stainless steel [1,8], but have very sharp edges that core septa. Inserting solid samples or capillary tubes into an inlet for thermal desorption needs the septum head to be removed, and retrieving them requires the septum and septum nut to be replaced by other hardware [9][10][11][12][13].…”

“…The rubber septa of split-splitless GC inlets limit how samples can be introduced; 32-gauge on-column needles are too flexible to penetrate unmodified septa [1], and needles thicker than about 1.5 mm make holes that are too large to re-seal. This limits the diameter of SPME and inneedle traps, which restricts the volume of SPME absorbents to less than a microliter and the mass of adsorbents to a few milligrams, and in turn limits breakthrough volumes and limits of detection and quantitation [2,3].…”