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c/hplc·submitted 25 days ago by u/ewan_marchand

does integration actually matter or is it forum lore at this point

Methodbranch of 8 comments

does integration actually matter or is it forum lore at this point. I am not trying to be the "source?" guy. I would just like a source. 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…

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8 comments, started 24 days ago
u/enzo_petrescu78 points·24 days ago

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

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u/hydration_hank62 points·24 days 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/medutest_mel14 points·23 days ago

UV response is not uniform across species.

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

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u/elodie_grimaldi5 points·23 days ago

214nm sees the peptide bond, 280nm sees the aromatics

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u/peak_area_peteMOD59 points·24 days ago

Retitled: the original claimed a comparison the post does not actually make.

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u/ewan_marchandOP45 points·23 days ago

two labs, two gradients, two honest answers

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u/enzo_petrescu40 points·23 days ago·edited

Correcting myself upthread: I said the gradient was linear and looking again it has a hold in the middle.

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u/samir_falk31 points·23 days ago

LC-MS for identity, UV for relative quantity

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