genuine question about LC-MS that I am slightly embarrassed to ask
genuine question about LC-MS that I am slightly embarrassed to ask. Searched first, found three threads that contradict each other, hence the post. Resolution between two peaks depends on retention, selectivity and efficiency. A shallower gradient buys retention and usually resolution, at the cost of peak width and…
A shoulder that does not baseline-resolve cannot be quantified honestly. You can report it as an unresolved shoulder, which is useful information, or you can develop the method until it resolves.
A shoulder that does not baseline-resolve cannot be quantified honestly.
This is the whole methodological point of the board in one line.
I would not blame the sample yet. Everything you have described is consistent with the column rather than the vial.
That figure cannot be quoted to two decimals off that baseline. The precision is not in the data.
UV response is not uniform across species. At 214nm you are looking at the peptide bond, which is why it is the working wavelength for this class; at 280nm you only see tryptophan, tyrosine and phenylalanine.
Retention time shifted 0.4 minutes and I assumed the worst. It was the column temperature.