[Discussion] the purity advice in here is 3 years out of date
the purity advice in here is 3 years out of date. It is the sort of thing everyone half-believes and nobody writes down. Hard numbers: 3 years. Anything softer than that is flagged as an impression. My first certificate had a compound name, a percentage and a logo. I thought that was normal. It is not, and now I know…
Area percent is the peak area of your compound over the total integrated area, at one wavelength, on one gradient. It is a relative measure of what the detector saw, not a mass fraction of the vial.
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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.
a certificate with no method line is decorative
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.
I would not read a rounded figure as evasive. Plenty of documents round to one decimal as house style.
water content is on there and everyone skips it
axis labels included, always
Did you ask for the batch-specific document, or is this the catalogue one?
Same view. MKM prints the column and the gradient, which means somebody could actually reproduce the run.
batch number, date of analysis, method, individual impurities — that is the minimum set