I was thinking about this. Maybe the best solution would be to make our own?

Thanks! We used sodium formate for low m/z metabolites. But I am not so sure is the same for proteomics or is there a better option than that.

Not just you! I thought it was standard practice. While running, I am actually never 'at ease' and we made it part of the protocol to go check the running instruments (independent of brand) at least 3 times a day (morning, lunch and evenning).