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

does method development actually matter or is it forum lore at this point

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Asking properly rather than in a comment on somebody else’s thread: does method development actually matter or is it forum lore at this point. Retention time shifted 0.4 minutes and I assumed the worst. It was the column temperature. Ran a blank after a high-concentration injection and found the carryover I had been…

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8 comments, started 1 year ago
u/runa_cabrera85 points·1 year ago

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.

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u/adaeze_batistaOP65 points·1 year ago

a blank injection between samples costs four minutes and settles most arguments

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u/ewan_tulloch40 points·1 year ago·edited

a blank injection between samples costs four minutes and settles most arguments

Adding one practical thing — run the blank. It answers this before anyone has to argue about it.

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u/rina_bergstrom45 points·1 year ago

Small fix — 214nm, not 210. It matters for the comparison you are making with the other run.

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u/anya_erdogan49 points·1 year ago

UV response is not uniform across species. At 214nm you are looking at the peptide bond, which is why it is the working wavelength for this class; at 280nm you only see tryptophan, tyrosine and phenylalanine.

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u/ewan_tulloch11 points·1 year ago

reproducibility beats resolution if you only get one of them

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u/ignacio_vanhecke56 points·1 year ago·edited

What did system suitability look like on that sequence?

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u/fatima_yildiz15 points·1 year ago

baseline choice is a decision, not a measurement

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