Home › Learn › Questions › Certificates
Is chromatographic purity the same as peptide content?
The short answer
No. Chromatographic purity is a percentage of detected peak area — a ratio among absorbing species. Peptide content is an absolute measurement of how much peptide the vial holds, expressed in milligrams. A sample can show 99% chromatographic purity while containing significantly less peptide mass than its label claims, because water and counter-ions are not counted.
In detail
Think of purity as answering "how clean is what I can see" and content as answering "how much is actually there". They are independent, and both can fail independently.
Public community datasets consistently show that quantity against label claim is the more common failure mode in the research-peptide market, not identity. That makes the milligrams-per-vial line the one worth reading first on most reports.
Our standard test reports both: chromatographic purity at UV 214 nm, and duplicate quantification in milligrams per vial against a reference standard.
Related questions
People also ask
Iberian Analytical opens in Q1 2027 — €99 per test, 48–72 h target, and every result published in a public database, mandatory and free. Nothing is sold on this site today. Leave an email and we will write once, when the laboratory starts issuing certificates.
Have a question that is not here? Write to [email protected] — we answer in public, and every real question becomes a page.