“99% pure” is the headline number on most peptide certificates — but what does it actually measure?

What HPLC measures

Reverse-phase high-performance liquid chromatography separates a sample into its components and reports the target peptide as a percentage of the total. A single tall, sharp peak indicates a clean compound.

Why ≥99% is the benchmark

Research reproducibility depends on knowing your material. ≥99% purity minimises confounding impurities from synthesis.

What the remaining 1% is

Usually closely related synthesis by-products (truncated or deletion sequences), not contaminants — but only an identity check (mass spec) confirms it.

See real numbers

Every NOVA Labs batch is HPLC-tested; browse the figures in the COA browser.

For research use only. Not for human or veterinary use, consumption, or diagnostic application.