High-performance liquid chromatography (HPLC) pumps a liquid sample through a column packed with fine particles. Each component of the sample is held back by the packing to a different degree, so the components leave the column at different times and are measured one after another by a detector.
Peptides are almost always analysed by reversed-phase HPLC, in which the packing is hydrophobic (most often C18-bonded silica) and the mobile phase moves from mostly water to mostly acetonitrile over the run. More hydrophobic molecules are held longer. A UV detector set near 214–220 nm, where the peptide bond absorbs, records each eluting component as a peak.
The result, a chromatogram, is the basis of the chromatographic purity figure reported on a certificate of analysis.
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For in vitro laboratory research only. Not for human or veterinary use. This library describes chemistry, analytical methods and published laboratory research; it gives no guidance on use in people or animals.