[COA] what does "related substances 1.4%" actually mean for my vial
Posting this because the title is the whole finding — what does "related substances 1.4%" actually mean for my vial — and a number without its method is a rumour. 1.4%. Those are measured, not estimated, and not rounded up in my favour. Started keeping a folder of every certificate I have been sent. The ones that…
Yes — and the reason to ask for the whole page is that the interesting parts are the ones people crop out to fit a screenshot.
Yes — and the reason to ask for the whole page is that the interesting parts are the ones people crop out to fit a screenshot.
Adding the bit that always gets missed: the lot on the vial has to match the lot on the page, or none of this applies to your material.
Disagree that a lower number is automatically worse. A conservative claim that survives testing is worth more than an optimistic one that does not.
Right, and net peptide content is where the counterion and the water go. Both numbers can be honest and very different.
Small fix — 214nm, not 280nm. It matters here because the impurity you are asking about barely absorbs at the longer wavelength.
That is the catalogue certificate rather than the batch-specific one. Same layout, completely different status.