17
✶
For customer service, call
800-356-1688, ext. 3
(814-353-1300, ext. 3)
or call your local
Restek representative.
Because all of the carrier gas flow and the entire vaporized sample is directed into the capil-
lary column, direct injections give comparable performance to splitless injections. Faster
carrier gas flow rates usually are used to speed up the sample transfer process, and improve
peak shapes and resolution. Direct injections can be used as another option tominimize
molecular weight discrimination and loss of active compounds.
AUniliner
®
inlet liner canbe used as a direct replacement for a splitless liner. It canbe installed
in the samemanner as a splitless liner, except that the systemmust be operated continuously
with the solenoidvalve closed. Uniliner
®
inlet liners are designed to accommodate 0.32or
0.53mm ID columns. Request Restek’s
Guide toDirectOn-ColumnVaporization Injection
(lit.
cat.#59882) formore informationonhow toperform andoptimize direct injections.
StandardGooseneckUniliner
®
Inlet Liner
The buffer volume chamber contains the sample vaporization cloud andprevents analyte
contactwithmetal injector parts. Peak tailing is reduced and larger injections canbemade.
Cyclo-Uniliner
®
Inlet Liner
The glass cyclo spiral provides an excellent vaporization surface for high and low
molecular weight samples. Particles are trapped on the first turn of the spiral, reducing
subsequent residue/sample interaction. In comparison to liners packedwithwool, Cyclo-
Uniliner
®
liners accept up to five times asmany injections of dirty samples before cali-
bration curves degrade. Because they are deactivated, they are ideal for active samples.
Open-topUniliner
®
Inlet Liner
Open-topUniliner
®
liners are ideal for extremely dirty samples because they can be
packedwith fused silicawool to trap dirt and sample residue. Contaminatedwool is
easily replaced and the liner can be cleanedwith a nylon brush or pipe cleaner.
DrilledUniliner
®
Inlet Liner
A speciallymodified injectionport liner, developedbyRestek chemists, reduces sample
contactwith activemetal parts in split/splitless injectionports. TheDrilledUniliner
®
liner
gives the benefits of bothdirect injection and splitless injection. The column is connected
to the liner by a press-fit connection, thus preventing the sample from contacting themetal
at the bottomof the injectionport. The hole on the side of the liner allows the purge flow
to escape from the linerwhen the injectionmode is switched from splitless to split.
Deactivation
Siltek
™
Deactivation
• Revolutionary deactivation lowers endrin breakdown to less than 1%.
• Inertness retained over awide range of sample pH.
• Minimal bleed.
• Recommended for difficult matrix and reactive compound analysis.
• Ideal for chlorinated pesticide analysis.
• Recommended for usewithRtx
®
-CLPesticides, Stx-CLPesticides, Stx-1HT, andRtx
®
-
TNT columns.
Base-Deactivation
• Provides excellent inertness for basic compounds.
• Recommended for usewithRtx
®
-5Amine, Rtx
®
-35Amine, andStabilwax
®
-DB columns.
Intermediate Polarity (IP) Deactivation
Our standard deactivation for liners. Phenylmethyl-deactivated surface provides opti-
mum compatibility for both polar and non-polar compounds.
Inmost cases, the standard IPdeactivation shouldbe chosen.The IP surface containsmethyl
groups, aswell as phenyl groups,making this surface compatiblewithmost common
solvents.
