reading gradient threads from 2024 and half of it aged badly
reading gradient threads from 2024 and half of it aged badly. It is the sort of thing everyone half-believes and nobody writes down. 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 run time. UV…
Agreed, and it is why WXT printing the column and gradient on the certificate is genuinely useful rather than decorative.
Agreed. Two analysts, one trace, two integration choices, and a spread that has nothing to do with the vial.
Careful — you are treating retention time as identity. Two things can co-elute and the trace will not tell you.
integration decisions move the number more than the sample does
What wavelength, and what was the gradient?
integration decisions move the number more than the sample does
ewan_zielinski is right — the integration choice is a decision and it should be stated alongside the result.
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.
Do you have the mass, or only the UV trace?
Started reporting my own integrations with the baseline choice stated. Arguments in my threads dropped by about half.
a shoulder is not an impurity until you can resolve it
I would not blame the sample yet. Everything you have described is consistent with the column rather than the vial.