reading LC-MS threads from 2024 and half of it aged badly
Thinking out loud about this: reading LC-MS threads from 2024 and half of it aged badly. Mass spectrometry answers identity. UV purity answers relative quantity under the run conditions. A document with one and not the other is answering half the question, and the half it answers should be stated. Carryover from a…
The system suitability argument, since it comes up whenever somebody posts a number without one.
Before the sample result means anything, the instrument has to be shown to be fit that day: replicate injections with an acceptable RSD on area, a tailing factor inside limits, adequate plate count, and a resolution check between the pair you care about.
None of that is exotic and all of it is routine in a laboratory that reports for a living. Its absence does not mean a number is wrong; it means the number is unanchored, and unanchored numbers should not be quoted to two decimal places on this board.
Same view — reporting the gradient is what makes a result checkable rather than merely stated.
Yes. Retention time is a hypothesis about identity. Mass is the answer.
Do you have the mass, or only the UV trace?
axis labels or the trace is decoration
reproducibility beats resolution if you only get one of them
Same method at both labs, or two different gradients?