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- Posts: 14
- Joined: Thu Jul 05, 2018 5:27 am
First of all thank you for receiving me on this quite interesting forum. I think this forum will be my benchmark for my work.
I'm writing you because I'm experiencing some issues with my quantification standard I currently use to evaluate peaks eluted at hplc and analysed in ESI MS positive ion mode.
In particular, I observe a time-dependent decrease in the reserpine-peak area (my standard) and an increase in the areas of two peaks before and after the elution of the standard. The m/z of reserpine is 609.28. the m/z under that "satellite" peaks is 639.29. There is a delta of 30.01 Da corresponding, maybe, to a CH2O.
Furthermore, I observe this reserpine modification randomly, and i'd like to identify the root of this problem in order to avoid it in the next analysis.
I don't think that the problem is instrumental, but I am strongly considering that there is something that trigger some kind of reaction in my vial. Another information is that I use a mix of reserpine and another standard ( one of the various types of organic): interestingly, irganox remains stable, whilst reserpine undergoes this hellish modification.
Does anyone experienced similar issues? How did you get rid of it? Do you have any clues?
Thank you very much