Varian 450-GC, User Manual

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AutoSamplers
Varian, Inc. User Manual 450-GC Page: 145
Plunger
Plunger
Barrel
Barrel
Retaining Nut Retaining Nut
Color-coded
Color-coded
Screw Hub
Screw Hub
Sealing Septum
Sealing Septum
Fiber
Fiber
Attachment Rod Attachment Rod
SPME Fiber SPME Fiber
Fiber Sheath
Fiber Sheath
(pierces septum (pierces septum
of sample vial
of sample vial
and GC injector)
and GC injector)
Fiber Sheath Fiber Sheath
Fiber Fiber
Attachment Rod
Attachment Rod
SPME Fiber
SPME Fiber
Injector Insert
To assure optimum results when desorbing a SPME fiber, it is important to use
the correct Injector insert. Use a straight, unpacked insert with an internal
diameter of 0.8 mm (P/N: 392611948 for the 1079 Injector). Smaller inserts do
not allow the fiber sheath to penetrate the Injector, while large inserts will
broaden early-eluting analytes.
The SPME fiber is mounted in the fiber sheath. During septum
penetration, the fiber is completely retracted into t he sheath f or
protection. A bl unt sheath with a relatively large diameter may result in
septum leakage. If you encounter frequent septum failure, use the
optional Merlin Microseal
TM
.
Figure 17: SPME Syringe
When performin g liq uid SPME, make sure that the fi ber sheath does NOT
contact the liqui d. This may result in carry-over.