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c/hplc·submitted 1 year ago by u/honest_syringe_pls

someone explain LC-MS to me like I have not read a paper in years

Correctionbranch of 7 comments

someone explain LC-MS to me like I have not read a paper in years. 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…

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7 comments, started 1 year ago
u/georgi_tamm25 points·1 year ago

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.

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u/rasmus_petrescu9 points·1 year ago

baseline choice is a decision, not a measurement

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u/rosa_sandvik3 points·1 year ago

LC-MS for identity, UV for relative quantity

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u/honest_syringe_plsOP2 points·1 year ago·edited

What wavelength, and what was the gradient?

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u/ahmed_rasmussen7 points·1 year ago

axis labels or the trace is decoration

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u/ferran_krastev6 points·1 year ago

ghost peak, check the plumbing first, it is always the plumbing

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u/hugo_bergstrom6 points·1 year ago

That is area percent, not mass percent. The trace cannot give you the second one.

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