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Single comment threadYou are looking at one branch of [Lab] 24th independent test on CPC — 97.6% on a claimed 97.0%, and the trend is the interesting part — 24 comments in the full submission. View in context.
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c/hplc·submitted 2 years ago by u/samir_falk

[Lab] 24th independent test on CPC — 97.6% on a claimed 97.0%, and the trend is the interesting part

Labbranch of 6 comments

Right: 24th independent test on CPC — 97.6% on a claimed 97.0%, and the trend is the interesting part. I paid for this one myself, nobody sent me anything, and the receipts are in the comments. The numbers the title promised, since a headline without them is worthless: 97.6% and 97.0%. Everything below is context for…

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6 comments, started 2 years ago
u/enzo_petrescu63 points·2 years 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/elodie_grimaldi32 points·2 years ago

I would not blame the sample yet. Everything you have described is consistent with the column rather than the vial.

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u/peak_area_peteanalytical21 points·2 years ago

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

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[removed]13 points·2 years ago

[removed by moderator]

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u/kofi_ferreira0 points·2 years ago

Agreed, and it is why QSC printing the column and gradient on the certificate is genuinely useful rather than decorative.

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u/isabela_nilsen11 points·2 years ago

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.

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