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c/coa·submitted 1 months ago by u/camila_lindqvist

[Lab] 6th independent test on HJ — 99.1% on a claimed 99.0%, and the trend is the interesting part

Labbranch of 8 comments

6th independent test on HJ — 99.1% on a claimed 99.0%, and the trend is the interesting part. One vial, one service, one member paying, which is the only kind of result this board should treat as evidence. The relevant figures are 99.1% and 99.0%, and they come from the same log I have kept the whole time. Related…

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8 comments, started 1 months ago
u/coa_collectorMOD197 points·1 months ago

Left up and flaired Explainer. This is the answer we keep linking, written properly.

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u/purity_pedantanalytical150 points·1 months ago

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/bastian_moreau53 points·1 months ago

HPLC-UV and LC-MS answer different questions

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u/yusuf_nakamura43 points·1 months ago

Disagree that a lower number is automatically worse. A conservative claim that survives testing is worth more than an optimistic one that does not.

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u/katrin_girard158 points·1 months ago

This. Area percent answers "what fraction of what the detector saw was the peak I wanted", and people read it as "how much peptide is in the vial".

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u/tomas_lehtinen41 points·1 months ago·edited

the lot on the vial has to match the lot on the page

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[removed]19 points·1 months ago

[removed by moderator]

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u/priya_palacios110 points·1 months ago

Agreed on asking for the storage condition. It is one line and it changes how you read the entire stability claim.

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