HPLC

High-Performance Liquid Chromatography (HPLC) is an analytical technique that separates the components of a mixture by pushing it through a column under high pressure. Each component elutes at a characteristic time, producing a chromatogram of peaks.

For research peptides, HPLC is the standard way to express purity: the main peak’s area is compared to the total, and purity is reported as a percentage (for example, ≥98%). A clean chromatogram with a single dominant peak indicates few impurities.

Publishing the raw chromatogram — not just the number — is the most transparent form of purity reporting, because it lets an outside reader judge the data directly.