Centre de ressources / ChromaBLOGraphy / Troubleshooting GC Columns – a Methodological Approach – Part 2

Troubleshooting GC Columns – a Methodological Approach – Part 2

23 Nov 2022

In my previous post, Troubleshooting GC Columns – a Methodological Approach – Part 1, I provided questions which you should ask yourself to try to determine what may be causing the chromatography issue you are experiencing.   In this post, I will provide links to Restek videos and literature (when available) which may help you fix specific issues.

New column (no samples/matrix injected into the column)

1. How old is the column?

GC columns do not have an infinite shelf life.  If unused, GC columns should have a shelf life of two years or more if stored properly (in a climate-controlled laboratory or warehouse).

2. Was the column installation verified to be leak free?

Always have clean, inert carrier gas flowing through the column and always leak check the column before heating it.  At temperatures greater than approximately 80°C, oxidation may begin to occur if exposed to air.

3. Have the carrier gas traps/filters been inspected and confirmed to be in good working order?

4. Was the column purged long enough to remove all traces of air (oxygen) before heat was applied?

5. How exactly was the column conditioned?

6. When a column test mix was injected/analyzed, how did the peak shapes, responses, retention times and baseline compare to the original QA column test chromatogram that was supplied by the manufacturer?

Used column (samples/matrix have been injected into the column)

1. How old is the column?

It may not be possible to accurately determine an expected lifetime for a column unless experimental data has been generated in the past for the same type of column for the same type of analysis. 
Generally speaking, for a similar analysis/method, a non-polar or low-polarity column will often last longer than a mid or high polarity column.  In the link below, see Stationary Phase.  The non-polar columns are on the left and polarity increases as you move towards the right.

2. Has this column ever worked well for the current analysis, or for any other analysis?

3. If the column did work well in the past, is it installed into that exact same instrument?

4. If the instrument has multiple injection ports and/or detectors, have the column positions been switched?

5. If the column had been working well in a particular instrument and now is not, what has changed?

6. How quickly did the change take place from working well to working poorly?

7. Which GC maintenance steps were necessary to improve the column’s performance?

I hope you have found my two posts on Troubleshooting GC Columns – a Methodological Approach helpful and informative. Let me know if you have any questions.