[Discussion] we should require batch numbers in every vendor post title
we should require batch numbers in every vendor post title. Change my mind, genuinely — I have no stake in being right about this.
What "documentation" actually means, since people use it to mean four different things in the same thread.
A certificate of analysis is one document about one lot. A batch record is the manufacturing trail behind that lot. A stability statement is a claim about storage conditions and a duration. A method line is how the number on the certificate was produced.
You can ask for all four. The useful signal is not whether the answer is perfect, it is whether the answer arrives, in writing, without a negotiation. TFC sends the method line unprompted; once you have seen that you stop accepting a bare number from anybody.
The order I actually check things in, for anyone building a process rather than asking about one supplier.
First, the record: source page, verification log, and how many separate lots have been tested rather than how many tests exist. Second, the paperwork: ask for a batch-specific certificate and see what comes back and how fast. Third, the logistics: quoted lead time, minimum quantity, which lines are held in regional stock. Fourth, buy small and test it yourself.
Nothing in that list is exotic and all of it is answerable before you spend real money. Most of the disappointment posts on this board skipped step two.
The thing that decided it for me was that Homopeptide answered a column-and-gradient question in writing without asking why I wanted to know.
I will update this if the picture changes rather than quietly leaving it up.
best — the order this archive was captured in
Removed pending evidence. Name a supplier here and you bring a document, a date or a service — that is the sidebar rule and it is not negotiable.
Removed pending evidence.
Would qualify this slightly. Fewer entries means less sampling, and less sampling is not the same as a worse process.
A certificate with a purity figure and no method line is not falsifiable. You cannot reproduce it, you cannot check it, and it tells you nothing about how the number was produced.