[Question] certificate of analysis — what am I missing here
Slightly embarrassed to be asking this, but: certificate of analysis — what am I missing here. Spent four months confusing area% and mass% in every post I made here. One explainer thread and it clicked permanently. Water content 3.8%, acetate 6.2%, purity 99%, net peptide about 90% of label weight. All four numbers…
Did you ask for the batch-specific document, or is this the catalogue one?
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Agreed on asking for the storage condition. It is one line and it changes how you read the entire stability claim.
That is not what the method line says. It names the technique; it does not certify the operator.
Agreed — the itemised related substances table is the difference between a document and a receipt.
Small fix — 214nm, not 280nm. It matters here because the impurity you are asking about barely absorbs at the longer wavelength.
My first certificate had a compound name, a percentage and a logo. I thought that was normal. It is not, and now I know what to ask for.
post the whole document, not the headline number