Innovators of High Resolution
Chromatography Products
the
in this issue
MTBE &Oxygenate Analysis Using an
Rtx
®
-VGC Capillary GCColumn
…pg. 6–7
NewAnalytical ReferenceMaterials
…pg. 8–9
Tips forMaximizing
HPLC Column Lifetime
…pg. 10
Fast GC Analysiswith the
GC Racer System
…pg. 11
Inert Inlet System Improves Responses
for Chlorinated Pesticides
…pg. 12–13
Analyzing Organophosphorus
Pesticides
…pg. 14–15
MerlinMicroseal
®
Septa
…pg. 15
Behind the Scenes
…pg. 16
2002
vol.2
by Donna Lidgett, GCAccessoriesProduct MarketingManager
Leak-Tight Seal for Agilent GCs
Vespel
®
Ring Inlet Seals
Advantage
Vespel
®
Ring
Inlet Seals
…pg. 1–2
Cool Tools
…pg. 2
High-Speed Analysis of
Petrochemicals
…pg. 3
HPLC Analysis of
Preservatives
…pg. 4–5
In Agilent split/splitless injection ports, the inlet
seal sits at the base of the injector. Dirt, non-volatile
residue, septum fragments, and other undesirable
particles contaminate the inlet seal and decrease
analytical linearity. The only way tomaintain opti-
mum performance is by frequently changing the
inlet seal and ensuring the seal is leak-tight.
✔
Easy to use—Vespel
®
material seals the first time, every time, reducing variability
among operators.
✔
Better sensitivity—lower leak rate reduces detector noise.
✔
Savesmoney—prevents oxygen from permeating the carrier gas, increasing
column lifetime.
✔
Lessmaintenance—soft sealing area reduceswear on the injection port body.
Restek designed the Vespel
®
Ring Inlet Seal to
improve injection port performance on two levels.
First, the Vespel
®
Ring Inlet Seal is made from
high-quality stainless steel and features a Vespel
®
ring embedded into its face. This soft Vespel
®
ring
will not harm the critical seal on the bottom of the
injector body, and is outside the sample flow path,
for worry-free chromatography.
Second, the Vespel
®
Ring Inlet Seal is designed to
seal even after repeated temperature cycles and
without retightening the reducing nut! With tradi-
tional stainless steel inlet seals, it is difficult to
tighten to achieve a leak-tight seal. To determine
the variances between a traditional seal and the
new Vespel
®
Ring Inlet Seal, we compared the leak
rate for each type of seal at increasing torque
(Figure 1). Several inlet seals of each type were
Figure 1
The Vespel
®
Ring Inlet Seal achieves leak-tight seals even at low torque, reducing injection port
wear and the chances of damaging the injection port.
Torque (in lbs)
Leak Rate (Log
10
atm cc/sec.)
0 10 20
30
40
0.01
1E-3
1E-4
1E-5
1E-6
1E-7
1E-8
1E-9
1E-10
50
60
Vespel
®
Ring Inlet Seal
stainless steel
original equipment
inlet seal
new
patent
pending
