Understanding HPLC Testing

High-Performance Liquid Chromatography pushes a dissolved sample through a column packed with a specialized material. Different compounds travel through the column at different rates depending on how they interact with that material, so they exit — or 'elute' — at different times.

A detector records each compound as it emerges, producing a chromatogram: a chart of signal over time, where each peak represents a distinct component of the sample.

In a peptide purity analysis, the dominant peak is the target compound. Its area, as a percentage of the total peak area, is the reported purity.

Smaller peaks represent impurities — usually structurally related byproducts of synthesis. A clean chromatogram with one dominant, well-resolved peak is the visual signature of a high-purity preparation.

HPLC is quantitative, reproducible, and sensitive enough to resolve impurities present at fractions of a percent. For peptides specifically, reversed-phase HPLC separates compounds by hydrophobicity, making it exceptionally well suited to distinguishing a target sequence from its synthesis byproducts.

Every SFVLAB batch purity result is derived from HPLC analysis, documented on the batch-specific COA.