help me understand batch, I have read the wiki twice
Question in the title, detail here: help me understand batch, I have read the wiki twice.
The PDF creation date being later than the analysis date is usually a re-issue or a re-export. It is worth one question and it is not evidence of anything on its own.
Sent one vial to VendorInvestigate and PeptideMeter. 98.8% and a claimed 98.0%. Cost me more than the vial and I would do it again.
Started keeping a folder of every certificate I have been sent. The ones that itemise impurities are a small group and they are mostly the same suppliers.
If somebody has the same thing measured a different way, post it next to mine and we will see whether they agree.
best — the order this archive was captured in
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.
Ask what the stability statement was written against — temperature, light, and whether it was the lyophilised powder or the reconstituted solution. Those are three different claims.
Is water content on the document? It changes your concentration arithmetic.
Did you get the chromatogram or only the summary line?
Did you get the chromatogram or only the summary line?
milos_vanhecke has the distinction right — one is a fraction of the detector signal, the other is a fraction of the mass.
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".
Spent four months confusing area% and mass% in every post I made here. One explainer thread and it clicked permanently.
Reminder: a question about a document is not an accusation about a supplier, and posts that blur the two get retitled.
Batch number and date of analysis, are both on there?
That is the catalogue certificate rather than the batch-specific one. Same layout, completely different status.