Reading time: ~2 min · Part of the free certification in peptide science
An experimental result is only worth as much as the characterization of the material that produced it. Two questions structure quality control: is it what it claims to be? (identity) and how pure is it? (purity).
High-performance liquid chromatography (HPLC), typically reversed-phase (RP-HPLC), is the reference method for purity. The sample is separated according to each component's interaction with a hydrophobic column and a solvent gradient; each species elutes at a characteristic retention time and produces a peak.
How to read a chromatogram
- Main peak: corresponds to the target peptide. Purity (%) is calculated as the area of that peak relative to the total area of all peaks.
- Related substances: the smaller adjacent peaks are usually synthesis impurities —deletion, truncated or epimerized peptides— whose sum makes up the "rest".
- Reference standard: research material is handled at purities of ≥99% by HPLC; below that threshold the reliability of any study suffers. The catalog figure is a guaranteed minimum: the measured value of each batch is on its COA.
A clean chromatogram, with a well-defined dominant peak and minimal related substances, is the first visual evidence of well-made material.
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Go to the quiz →Educational content for scientific purposes. It distinguishes preclinical from clinical evidence and is not medical advice, diagnosis or a recommendation for use. NeoPeptidos products are sold labelled for research use only (RUO).