Splitless injection pulsed

An alternative to the pressure-pulse mode is the use of a temperature-programmable injector (abbreviated as PTV, CIS/KAS) which was initially applied for the injection of large sample volumes [160] or for injection of toxaphene at a low temperature followed by a very fast temperature ramp. In this way toxaphene components can be volatized with a minimum of thermal stress [161]. Although no detailed study has been conducted with toxaphene, this technique should result in less degradation than a splitless injection at a constant high temperature. 

Split/splitless Capillary Split Pulsed splitless Splitless Pulsed splitless High concentration High concentration Low concentration Low concentration New technique (>2 tL) Useful with large injections (>2p,L) High sensitivity... 

More recent studies preferred injector temperatures of below 200°C to avoid decomposition in the splitless injector [146]. However, low injector temperatures increase the risk of an incomplete transfer of the sample onto the GC column. To overcome this problem, a pressure-pulsed injection has been suggested [125, 157-159]. Detailed investigations with single toxaphene components have shown that the response factors of less volatile components can be increased fourfold by this technique using an injector temperature of 230°C (see Fig. 9 for an example) [158,159],... 

Pulsed splitless Reduction of the residence time in the liner resulting in the decreased analyte degradation/adsorption and reduced matrix-induced response enhancement Larger injection volumes (limited by the liner size and solvent expansion volume) Potential transfer of nonvolatile matrix cx)mponents further into the column... 

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