Guides
How to read peptide lab paperwork
Plain-language explanations of the documents and tests behind a purity claim. Each guide lists the primary sources it relies on.
Endotoxin and sterility testing: what a purity number leaves out
An HPLC purity figure covers peptide-related impurities only. Endotoxin and sterility are separate lab tests with their own methods and units.
How to read a peptide certificate of analysis (COA)
What each field on a peptide certificate of analysis means, how in-house and third-party reports differ, and the signs of a weak COA.
How to verify that a peptide lab report is real
Six checks that show whether a peptide lab report came from the lab named on it, is unaltered, and matches the lot in hand.
HPLC purity explained: what "99% pure" does and does not mean
HPLC purity is the main peak's share of the detector signal on a chromatogram. See what "99% pure" covers and what it leaves out.
Mass spectrometry for peptides: how identity is confirmed
How mass spectrometry confirms a peptide's identity by comparing observed and expected mass, and what a mass match cannot show.
What "research use only" means on a peptide label
What a "research use only" peptide label does and does not change under US federal law, based on FDA rules and warning letters from 2024 to 2026.