Re: about isotopes
Reply #15 –
I wouldn't say that your data is behaving badly. I've had two other friends report that same and talked to quite a few people that say that they get similar results. Apparently the orbitrap is the best machine for this work ( of regular MS's) and even there it can be off by quite a bit too.
You might want to have a look at the following paper which trys to come up with a method for quantifying the errors from the MS.
http://pubs.acs.org/doi/abs/10.1021/ac101278x