[Method] 220nm vs 214nm and what you lose at each
220nm vs 214nm and what you lose at each, written plainly and without the jargon that usually swallows this topic.
Gave the same trace to two people I trust and got two integrations about a point apart. That was the most educational afternoon I have had here.
Carryover from a previous high-concentration injection looks exactly like a small impurity. The blank injection is four minutes and it removes the ambiguity entirely.
Chased a ghost peak for three weeks. It was the plumbing. It is always the plumbing.
Sceptical readings welcome. The confident ones are the ones I distrust.
best — the order this archive was captured in
System suitability — repeat injections, tailing factor, plate count, RSD on area — is what tells you the instrument was fit for the measurement that day. Without it, the purity figure is unanchored.
Is that baseline drawn by the software or by hand?
Yes. Retention time is a hypothesis about identity. Mass is the answer.
Disagree. Inter-lab spread of a point or two on this assay is ordinary and calling it a discrepancy misleads people.
I would not blame the sample yet. Everything you have described is consistent with the column rather than the vial.