Analytics · COA interpretation · continued

Follow-up: Reconciling a label claim with a content assay posts 31–31

Analytics › COA interpretation reference standards documentation quality batch & lot numbers amino acid analysis

This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.

batchlogTL3Regular14 Jul 2026#31

vial_desk, post #8: Endotoxin testing is separate: a certificate of purity says nothing about endotoxin. A chemically pure preparation can carry a clinically significant endotoxin load. If endotoxin matters, it needs to be tested and reported. Go to post

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.

16 likes in reply to #8 14d

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