Peptide Expert Q&A
QA-05Updated 2026-05-19

What does '99% HPLC purity' actually mean?

It means that High-Performance Liquid Chromatography analysis shows ≥99% of the material is the intended peptide sequence, with less than 1% impurities — the pharmaceutical-grade benchmark for research peptides.

High-Performance Liquid Chromatography (HPLC) separates a sample into its components based on how each one interacts with a chromatography column. The resulting chromatogram shows peaks for the target peptide and for any impurities.

"99% HPLC purity" means that, by area under the curve, ≥99% of the material in the vial is the target peptide sequence. The remaining <1% is residual synthesis byproducts, truncated sequences, or salt.

Why this number matters:

  • A 92% pure peptide contains 8% of unknown sequences. Any experimental result you observe could be caused by those unknowns rather than the molecule you intended to study.
  • The whole scientific value of a peptide is its specificity — a low-purity peptide loses that value.
  • ≥99% is the pharmaceutical-grade benchmark; anything below is research-grade in name only.

ADAM Molecular Research discards sub-99% cuts during purification rather than blending them into a "close enough" final product. See The AMR Standard for our full QC chain.