Post Tue Apr 03, 2018 8:53 pm

Mass response changes between consecutive days

Dear all,

I am happy to collect your feedback on an issue! Do you observe changes in instrument mass response on consecutive days and, if yes, how do you go about it?

Attached is the example from the other day - clearly 140Ce becomes the brightest bead channel on day 2, instead of 153 Eu. The bead normalization (NolanLab Matlab) fails to correct for this and this is likely having an impact on the data. What's even more worrying is that there are 40 other channels in there where I have no control over what's happening!

Has anyone looked into this and can comment on the impact it might have on the actual data? Additionally, maybe someone more knowledgeable could tell me why bead normalization fails to correct for this and fails to maintain relative relationship between the bead channels as set at the beginning of the acquisition?

Best,
Vinko
Attachments
before and after.jpg