War story: the COA batch number did not match the vial label

Logging this because it's exactly the kind of thing that's easy to miss. Got a new batch in, pulled the COA, and the batch number on the certificate didn't match the number printed on the vial label. One digit off.

Turned out to be a paperwork mix-up on a shipment that included two batches — the right COA existed, it was just the wrong file attached. But until that's confirmed, the rule is simple: if the COA batch doesn't match the vial, you don't use the vial. You stop and you ask.

Anyone else caught a mismatch like this? What's your verification step?

Textbook catch. The batch-number match between COA and vial is the very first thing I check, before I even read the purity. If those two numbers disagree, nothing else on the certificate matters yet.

Had the identical thing — two batches in one shipment, COAs swapped in the email. Supplier sorted it within the hour once I sent photos of both vials and both certificates. The photo-everything habit pays off precisely here.

This is exactly the kind of thing worth flagging to the supplier and worth posting here so others recognise it. "COA batch ≠ vial → stop and ask" is a great rule. Thanks for writing it up.

Glad it resonated. Consensus seems to be: match the batch number first, photograph both, stop until it's reconciled. Adding that to the verification checklist thread.

Adding to the war stories: caught a one-digit batch mismatch at 7am, pre-coffee, which means the verification habit works even when I personally do not. That's the entire point of a habit.

Mine matched perfectly and I STILL triple-checked, because this thread now lives in my head. You've all made me a better and considerably more paranoid researcher. Thank you? I think?

Want to join the discussion?

Related discussions

How to read a New-U COA (pinned reference)

First third-party report — sanity-check my read?

Total newbie: what does "area percent" actually mean?

How to actually read an HPLC purity report

Area percent vs weight percent on a COA — what is the difference?

PRECISION. PURITY. PERFORMANCE.

Research peptides at >99% HPLC-verified purity, third-party tested by Janoshik Analytical & Freedom Diagnostics, with Certificates of Analysis published per released batch. Supplied strictly for laboratory research use.

Shop

All research compounds

Price list

Where to buy peptides

Research