I use an AbSciex 4000 and recently lost peaks on a single compound in a 45 compound method. I’ve tried optimization manually and automatically. Help?

22 February 2018 1 4K Report

My buprenorphine has gone to crap. It’s one analyte in a panel of 45, nothing else has lost peak shape like this. My sensitivity has gone down for all compounds (ordered a new electrode hoping that will solve the problem but if anyone has suggestions for that as well I’ll take them!). Anyway, I have done manual tuning and compound optimization for Bup and it changed the CXP from 2 to 12...this did not help when I applied it to the method and gave it a run. There was virtually no change. I am at a loss and hoping someone can give me some ideas of what to try! Any help is appreciated!!

Jonalynn Masters

Here are photos of the chromatography for Bup and Pregab..same method, same run..

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