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Single comment threadYou are looking at one branch of reading water content threads from 2024 and half of it aged badly — 28 comments in the full submission. View in context.
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c/coa·submitted 6 months ago by u/blunt_coldbox29

reading water content threads from 2024 and half of it aged badly

Questionbranch of 7 comments

reading water content threads from 2024 and half of it aged badly. It is the sort of thing everyone half-believes and nobody writes down. Net peptide content is the fraction of the powder that is actually peptide once counterion, water and residual solvent are accounted for. A 99% pure acetate salt can still be about…

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7 comments, started 6 months ago
u/laila_yilmaz122 points·6 months ago

The PDF creation date being later than the analysis date is usually a re-issue or a re-export. It is worth one question and it is not evidence of anything on its own.

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u/stablecoin_steve101 points·6 months ago·edited

Same view. WXT prints the column and the gradient, which means somebody could actually reproduce the run.

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u/wrong_network_w84 points·6 months ago

Small fix — 214nm, not 280nm. It matters here because the impurity you are asking about barely absorbs at the longer wavelength.

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u/emeka_beaulieu67 points·6 months ago·edited

Correction: that is net peptide content, not purity. Different number, different meaning, and the document says so if you read the row label.

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u/fatima_wojcik30 points·6 months ago

the related substances line is where the story is

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u/aleksi_eriksen-7 points·6 months ago

the counterion is part of the mass you paid for

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u/hugo_bergstrom44 points·6 months ago

post the whole document, not the headline number

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