TFA salt vs acetate salt on a peptide COA, assessed
What 'TFA salt' or 'acetate salt' on a peptide COA records, why vials arrive as TFA salts, and how residual TFA is measured, per a 2025 ETH Zurich paper.
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Assessments
Accreditation marks on a peptide test report: A2LA, ANAB and the ILAC/IAF merger, assessed
A logo on a certificate of analysis is not a purity grade. Assessed: what an ISO/IEC 17025 accreditation attests, why scope is the whole of it, and why the mutual-recognition line printed on reports is mid-rename.
Bacterial endotoxin testing, assessed as documentation a purity figure cannot supply
A percentage by HPLC is a chemical result. Endotoxin is a microbiological one, with its own method, its own calculated limit and its own report. Assessed on what a bacterial endotoxins test records and what it leaves open.
'Research use only' is a use statement, not a quality grade
The most-printed phrase in research supply carries no method, no measurement and no issuing body. Assessed on what it commits a seller to, how regulators have read it, and which fields on a label do the work instead.
FDA's 503B Bulks List, assessed as a document rather than a verdict
A public, dated, numbered federal docket that circulates as though it were a register of approved substances. Assessed on what the notices record, how the process moves, and how little of it bears on a research-supply purchase.
Lot traceability and vial labelling, assessed across the category
The label on a lyophilised vial is the only documentation that physically travels with the material. Assessed on what the category prints, what it omits, and what that costs a buyer.
The vendor-published certificate of analysis, assessed as evidence
The COA is the central document in research supply and the least examined. Assessed on what it actually establishes, what it leaves open, and how far a buyer can rely on it.
