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c/coa·submitted 2 months ago by u/blunt_coldbox29

why does nobody talk about area percent

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why does nobody talk about area percent — that is what I am asking, and I have already read the wiki twice. Water content 3.8%, acetate 6.2%, purity 99%, net peptide about 90% of label weight. All four numbers honest, and I had to read it twice. Started keeping a folder of every certificate I have been sent. The ones…

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u/ignacio_silva0 points·2 months ago

Not quite. Two labs with different gradients can resolve a close-eluting impurity differently and both be reporting honestly.

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u/priya_palacios1 point·2 months ago

Pushing back a little: a missing field is usually presentation, not concealment. Ask for the full document before drawing conclusions.

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u/gastric_emptying_g1 point·2 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/wanjiru_varga1 point·2 months ago·edited

Is water content on the document? It changes your concentration arithmetic.

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u/liv_nkemelu1 point·2 months ago

Did you ask for the batch-specific document, or is this the catalogue one?

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