Sourcing · Vendor reports

Follow-up: Reporting a discrepancy without making an allegation

Sourcing › Vendor reports certificate of analysis disputed third-party testing Janoshik Analytical documentation quality

w.moreauTL2 Moderator9 Aug 2024#1

Reporting a discrepancy without making an allegation Writing it up because I had to work it out twice and would rather nobody else did.

Structured report rather than an opinion, following the format the maintainers asked for.

Compound: retatrutide
Independent testing: Janoshik
Method as reported: reversed-phase HPLC, 214 nm
Result: 97.7% area
Certificate figure for the same lot: 98.1%

I am not drawing a conclusion about the supplier from one lot and I would ask that nobody else does either. I am adding a data point to a record.

44 likes 2y

sa.okonkwoTL2 Moderator5 Nov 2024#2

Lot matching: confirm the lot number on the certificate matches the lot number on the vial. A result from a different lot is not evidence about your vial.

11 likes 21mo

m.lindqvistTL2 Moderator6 Jan 2025#3

Coming back to the opening post, because the follow-up matters more than the original answer.

Two things before anyone answers the substance.

First, the context in the first post is clear and specific. Second, the question is framed so that an answer can actually address it. Both are the norm here and both matter more than they sound.

1 like 19mo

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