Specification in the result column: why that is a meaningful error — the long version
A test date preceding a manufacturing date is a clerical error until somebody explains otherwise, and asking is cheap. Most such things are transcription.
I have written this out at length because the short version keeps being misread.
The arithmetic in post #10 is right; the assumption feeding it is the part to check.
A certificate is a statement by its issuer that a defined test was performed on a defined lot and produced a defined result. That is all it is, and it is not nothing.
Nothing above should be read as advice about what anyone else should do.
When method identifiers are missing: "reversed-phase HPLC" is less specific than "reversed-phase HPLC at 214 nm on a C18 column with a 10 to 40% acetonitrile gradient over 20 minutes". The second lets someone reproduce the analysis. The first does not.
The distinction between release testing and characterisation is one industrial documents make and retail ones usually do not. It is the difference between "we tested every lot for this" and "we established this once".
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This topic was referenced in
- A checklist for reading a certificate in under two minutesAnalytics › COA interpretation · 46 replies
- Coming back to: Purity assay versus content assay: two different numbersAnalytics › COA interpretation · 77 replies
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