[Meta] proposal — a flair for related substances posts
Housekeeping: proposal — a flair for related substances posts. 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 that itemise impurities are a small group…
Area percent or net peptide content? They answer different questions.
Spent four months confusing area% and mass% in every post I made here. One explainer thread and it clicked permanently.
Agreed on asking for the storage condition. It is one line and it changes how you read the entire stability claim.
Agreed — the itemised related substances table is the difference between a document and a receipt.
post the whole document, not the headline number
the counterion is part of the mass you paid for
That is the catalogue certificate rather than the batch-specific one. Same layout, completely different status.
net peptide content and purity are two different numbers on the same vial
Cosigning. The batch identifier is load-bearing, and a certificate that cannot be tied to the vial in your hand is not about your vial.
batch number, date of analysis, method, individual impurities — that is the minimum set
HPLC-UV and LC-MS answer different questions