Choosing the Proper Ferrules for Your Capillary GC Column

Each GC instrument manufacturer requires a ferrule with different dimensions; hence, you may find that ferrules are usually not included in the box with a supplied capillary column. Additionally, mass spectrometer detectors may require the use of a ferrule dimension that is different from that used for the injector end of the column.

Why is it important to use proper fitting ferrules?
Improper nut/ferrule combinations create dead volume (empty space between the ferrule and injector port that is not swept by carrier gas). This may result in poor chromatography, as evidenced by fronting peaks and band broadening. Ensure that your chromatography is the best it can be by always using the proper nut/ferrule combination.

We hope the general guidelines below for 3 widely popular GC instruments will assist you in selecting proper ferrules.

Agilent^® Technologies or HP Instruments

Injector and Non-MS Detector End:

 If you are using the nut supplied with the instrument (with 6-7 threads; A), use Supeltex^® short ferrules (1). If you are using a Supelco ferrule nut adapter purchased before 2003 (5-6 threads; B) or a Supelco ferrule nut adapter purchased after 2002 (C), use Supeltex general purpose ferrules (2).

Trademarks

Supeltex is a trademark of Sigma-Aldrich Co. LLC
Agilent is a trademark of Agilent Technologies, Inc.
PerkinElmer is a trademark of PerkinElmer, Inc.
Varian is a trademark of Varian Medical Systems, Inc.