On-Column Injector

The on-column injector is supplied as standard equipment with the 910, 410 and 310 GC mainframes.

For most applications where a wide-bore 0.53mm capillary or 1/8" packed column is used, the on-column injector will give the BEST results. In most cases, the On-column injector is simpler and less expensive than heated injectors.

The on-column injector's low thermal mass and small size ensure that the syringe needle deposits the liquid sample well inside the column oven, so that as the column temperature increases, even high boiling point samples are completely vaporized. The on-column technique of sample introduction puts the sample into the bore of the column itself,         which is often more inert than a glass injection liner. Unlike split/splitless injection, on-column injection puts the entire sample volume into the column without the possibility   of boiling point discrimination or other uncertainties, and the gradual volatilization of the sample starting from a liquid droplet yields sharper peaks than flash vaporization followed  by re-condensation.

The on-column injector is supplied with carrier gas from the included electronic pressure controller (EPC), and the carrier gas is conveniently filtered with an internally mounted molecular sieve filter which can be baked out simply by flipping a switch on the GC's      front control panel. A second EPC is available for operating a column connected to a gas sampling valve (or for backflushing) without the injector fitting. Also available is a second injector fitting connected to the first EPC for applications where two columns are used in parallel, sharing the same carrier gas pressure.