When a research peptide is described as high purity, that figure comes from analytical testing, not a marketing claim. Understanding how purity and identity are measured helps you evaluate the materials you work with. This overview is written for researchers and applies to in-vitro laboratory research only.
HPLC: measuring purity
High-performance liquid chromatography (HPLC) separates the components of a sample as they pass through a column. The target peptide appears as a peak; impurities and related substances appear as additional peaks. Purity is reported as the area of the main peak relative to the total – so a figure such as 99% means the target peptide accounts for at least that share of the detected material.
Mass spectrometry: confirming identity
Purity tells you how much of the sample is a single compound, but not which compound. Mass spectrometry (MS) measures the molecular weight of the peptide, confirming it matches the expected sequence. Together, HPLC (purity) and MS (identity) answer the two questions that matter: is it the right peptide, and how clean is it?
Why third-party testing matters
Testing carried out by an independent laboratory removes any conflict of interest – the party verifying the material is not the party selling it. Every Helixa Biotech compound is third-party tested by Testides and Peptide Test Canada, and each batch ships with a certificate of analysis you can review. Our guide on how to read a COA walks through what those documents show.
All materials are supplied strictly for in-vitro laboratory research and are not for human or animal consumption.