High Performance Liquid Chromatography of Proteins on a Hydroxyapatite Column

High performance liquid chromatography on a spherical ceramic type hydroxyapatite has been applied successfully for the separation of various kinds of proteins. Twenty-one proteins of various origin, having an isoelectric point of 3.3–11.0 and a molecular weight of 11,000–190,000 daltons, were loaded on the column and eluted by linear gradient of sodium phosphate at pH 6.8. The chromatography showed good resolution and high recovery for the proteins. The analysis of the retention behavior, relation between capacity ratio and physicochemical properties of proteins, showed a tendency that the capacity ratio of protein increased with the pI value of the protein.