High-Performance Liquid Chromatography (HPLC) is the most widely used analytical method for determining peptide purity. It separates compounds in a mixture based on their chemical properties, allowing precise identification and quantification.
When a Certificate of Analysis shows 99% purity via HPLC, it means that 99% of the material in the sample is the target compound, with only 1% or less consisting of related impurities or byproducts.
Key things to look for on a COA
A quality COA should include the HPLC method used, retention time, purity percentage, and batch number for traceability.
- Purity percentage should be 98% or higher for research-grade compounds.
- Retention time helps confirm compound identity.
- Batch numbers allow you to trace the specific production run.