HPLC stands for High-Performance Liquid Chromatography. It is the industry-standard analytical technique for determining the purity of synthetic peptides. When you see a purity percentage on a Certificate of Analysis (COA), it almost always refers to HPLC purity.
The technique works by dissolving the peptide sample in a solvent and pushing it through a column packed with a stationary phase material. Different molecules in the sample interact differently with the stationary phase, causing them to elute (exit the column) at different times.
The HPLC chromatogram is a graph showing detector response (usually UV absorbance at 220nm) over time. The main peak represents the target peptide. Smaller peaks represent impurities such as deletion sequences, truncated peptides, or oxidized forms.
A purity of 99.51% (as shown in our sample COA for Retatrutide RT10) means that 99.51% of the detected material is the target peptide, with only 0.49% total impurities. This is considered excellent research-grade purity.
When evaluating a COA, also check for mass spectrometry (MS) data, which confirms the molecular identity of the peptide by measuring its molecular weight.
Disclaimer: This article is for educational purposes only. All peptides are sold for laboratory research use only. Not for human consumption.