Guard column selection
Posted: Mon May 18, 2020 8:16 am
by starbuck
What are the things that must be taken into account when selecting a guard column for HPLC?
(e.g. same chemistry with your analytical column)
Please give reasoning for each one if possible :)
Re: Guard column selection
Posted: Fri May 22, 2020 3:47 pm
by James_Ball
Normally the same stationary phase is used on both guard and analytical as the guard is simply a disposable extension of the analytical column. If however there are specific interferences you need to trap you could use a different phase that is highly retentive to the interference but does not retain the target analyte.
Matching the diameter of the guard and analytical is important as you do not want to introduce band broadening by having a large diameter guard column and a small diameter analytical column, and use shortest length needed for the same reasons.