MontrealPhd wrote:
As the method is validated and it does the job quite well I think - for now - the method must not be touched.
The last degradation product elutes at ~32min. A short time afterwards the column is rinsed.
As I want my column to be free of any degradation, I'll need to rinse.
Validated and house-developed methods can be modified -even without validation as per USP 621 and FDA ORA documents. If you make minimal changes to your existing method, you may not need to do a full validation, just document everything.
Your run time is quite long, agree. And agree that you should work on modifying this now.
We used techniques like increasing flow rate (when pressure was low enough), increasing column temperature, faster flow and higher organic during wash out, faster flow during equilibration to help. Shorter or narrower i.d. columns of same packing material can help.