Chromatography Forum

Dear All,
This particular question is being raised with respect to Indian Pharmacopoeia. I did not find any suggestions on whether it is allowed to change the carrier gas (I want to use helium instead of nitrogen which is specified in pharmacopoeia). I am analyzing ethanol (95%) and would like to improve resolution in system suitability between methanol and acetaldehyde (NLT 1.5). With nitrogen, I am getting resolution of 1.0 with nitrogen.
If I change the gas to helium, do I need to perform method validation or can proceed with method verification?
Please help and suggest.

Best regards,

Aniket

Yes, you will need to demonstrate equivalency after figuring out your new flow rates etc. This is a significant undertaking - make sure you'd rather do the work than just replace a column or repack (if it's a packed column method).

That said, if you're going to switch, switch to Hydrogen! You'll save $$$ and possibly improve your resolution.