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

method development — 10 things I got wrong before I got it right

Explainerbranch of 7 comments

method development — 10 things I got wrong before I got it right. Change my mind, genuinely — I have no stake in being right about this. Bought a second-hand instrument and learned more in six months of fixing it than in three years of reading traces. Sent the same vial to PeptideMeter and VendorInvestigate. 99.2%…

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7 comments, started 1 year ago
u/kofi_ferreira45 points·1 year ago

Right. And a blank between injections settles the carryover argument before it starts.

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u/marit_mensaOP25 points·1 year ago

Is that baseline drawn by the software or by hand?

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u/hedda_ekstrom37 points·1 year ago

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.

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u/valeria_cardoso9 points·1 year ago

Chased a ghost peak for three weeks. It was the plumbing. It is always the plumbing.

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u/samir_falk19 points·1 year ago

Do you have the mass, or only the UV trace?

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u/two_mil_or_one14 points·1 year ago

area percent is relative to what the detector saw and nothing else

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u/naomi_antonsen4 points·1 year ago

a shoulder is not an impurity until you can resolve it

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