The interaction of proteins with hydroxyapatite. III. Mechanism

The mechanism of protein binding to and elution from hydroxyapatite (HA) has been established. Binding occurs both by nonspecific attraction between protein positive charges and HA and by specific complexing of protein carboxyls with calcium loci on the mineral. Elution can take place either as the result of the nonspecific ion screening of charges or by the specific displacement of protein groups from sites on the column with which they had complexed.