Abstract:
Biogenic and pathogenic mineral formations contain calcium phosphates. It is known that hydroxylapatite is
the main mineral component of bone tissue, tooth enamel, and dentin. The basis of the processes of mineralization
is proposed to be in the adsorption interaction of free amino acids and associated protein molecules
with inorganic components in body fluids and emerging phases. However, the mechanism of their interaction
is not fully understood. In this paper the adsorption of amino acids on the surface of hydroxylapatite has been
studied. The synthesis of calcium phosphates from solution has been carried out. According to the results of
XRD and IR spectroscopy it has been established that precipitation is represented by the phase of
hydroxylapatite. The adsorption of amino acids in a wide range of variation of their concentrations and the
pH of the solution has been investigated. It has been established that adsorption of amino acids on the surface
of hydroxylapatite reaches saturation. The effect of pH on the maximum adsorption of amino acids on
hydroxylapatitehas been considered. It has been established that adsorption of amino acids is described by the
Langmuir model. The result of IR spectroscopy confirmed adsorption. It has been determined by the sign of
the surface charge of the solid phase of hydroxylapatite. The values of the Gibbs energy have been calculated.
It has been revealed that the interaction of amino acids with the surface of the hydroxylapatiteis characterized
by physical adsorption.
