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GC Injectors
HeatedFlashVaporization Injector
• Desorptionof SPMEFibers
• ExtremelyDirtySamples
• Adjustable fromambient to 300°C
• IncludesOn-ColumnMode
This 8610D GC has a standard On-Column
Injectoronthefirstoven, andanoptionalHeated
FlashVaporization Injector on the secondoven.
HeatedFlash
Vaporization
On-Column
The SRI Heated Flash Vaporization Injector is useful for
applicationswhich require lash vaporization of the sample
prior to the column, such as desorption of SPME ibers or
injection of extremely dirty samples where the nonvolatile
residuemust be trapped in the injection liner.
The injector’s heater block can be thermostatted up to 300°C, and includes as standard equipment two
injector liners: an inert SilcosleeveTM liner, and an unbreakable stainless steel liner, which also allows for
on-columnmode.
TheHeatedFlashVaporization Injector option is anupgrade to an existingOn-column Injector. Twoheated
injectorsmay be installedon theModel 8610CGC, but only oneon the smallerModel 310.Where noneed
for a heated injector exists, SRI recommends using the standardOn-column Injector.
Heated Injection vs. On-column Injection: PROSandCONS
In the early days of GC, the column oven insulation was typically several inches thick. It was not then
possible to insert a syringe through the oven wall to deposit the sample on the column and be assured
that the sample would completely vaporize unless the injector was heated. On today’s SRI GC, the oven
wall insulation is much thinner. This allows the syringe needle to penetrate well inside the column oven,
thus depositing the sample into the bore of the column itself. As the temperature is programmed up, the
sample is completely vaporized. Even high boiling analytes such asC
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hydrocarbons chromatographwell
usingon-column injection, since the area of the columnwhere the sample is deposited follows the column
temperature and ultimately heats to a point where theC
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begins tomigrate down the column. There is no
need toemployaheated injector unless thesampleneeds tobesplit, or if thesampleneeds tobedesorbed
fromaSPMEiber. In fact, theheated injector has somedistinct disadvantages. The internal surfacesof the
injector liner aremore chemically active than the very inert interior of the column, so undesired adsorption
and tailing can result when the sample is violently expanded in the hot interior of the heated injector. Also,
the heated injector transmits some heat into the column oven because of its close proximity, making it
harder for the oven to cool down close to ambient temperature.
8690-0025
HeatedFlashVaporization Injector upgrade
8670-0072
NarrowboreSPME injector sleeve
