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c/coa·submitted 6 months ago by u/nabila_espinoza

[Lab] 10th independent test on ERP — 97.2% on a claimed 97.0%, and the trend is the interesting part

Labbranch of 6 comments

10th independent test on ERP — 97.2% on a claimed 97.0%, and the trend is the interesting part. That is the headline. The document, the batch and the service are below so you can argue with the method rather than with me. To save the first four comments: 97.2% and 97.0%. Asked for the storage condition behind the…

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6 comments, started 6 months ago
u/marisol_frisk54 points·6 months ago

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 85% peptide by mass.

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u/dario_vermeulen69 points·6 months ago

a total of 0.4% tells you less than four named impurities adding to 0.6%

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u/nabila_espinozaOP42 points·6 months ago

Correcting myself upthread: I said the date was missing and it is on the second page, which I had not scrolled to.

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u/nabila_espinozaOP42 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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