Posting this under the heading it deserves: A community side-effect dataset, with its response rate and biases Everything below is what sits behind that.
Working through the identity arithmetic and I would like it checked.
retatrutide has a monoisotopic mass close to 4731.3 Da. On an electrospray instrument I would expect to see the multiply charged series rather than the intact singly charged ion, so for the doubly charged species I calculate (4731.3 + 2 x 1.00728) / 2, and for the triply charged the analogous expression.
The observed values in the report sit within a few ppm of those. My question is what that actually establishes, because I have seen people treat a mass match as a purity result and I do not think it is one.