[Question] is 98.1% actually fine or am I being sold a rounding error
is 98.1% actually fine or am I being sold a rounding error, and before anyone asks: same batch throughout, single submission, no cherry-picking between services. The numbers the title promised, since a headline without them is worthless: 98.1%. Everything below is context for those. Sent the same vial to Janoshik and…
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.
I would not blame the sample yet. Everything you have described is consistent with the column rather than the vial.
Correcting myself upthread: I said the gradient was linear and looking again it has a hold in the middle.
ghost peak, check the plumbing first, it is always the plumbing
Area percent is the integrated area of your peak over the total integrated area at one wavelength on one gradient. Change any of those and the number changes without the sample changing.
Yes. Retention time is a hypothesis about identity. Mass is the answer.
Yes.
Agreed. And the corollary is that the method line on a certificate is not decoration, it is the number’s provenance.
two labs, two gradients, two honest answers
integration decisions move the number more than the sample does
How old is the column and roughly how many injections has it seen?