Hydroxyapatite Nanopowder Synthesis with a Programmed Resorption Rate

Abstract EN

A microwave, solvothermal synthesis of hydroxyapatite (HAp) nanopowder with a programmed material resorption rate was developed.

The aqueous reaction solution was heated by a microwave radiation field with high energy density.

The measurements included powder X-ray diffraction (PXRD) and the density, specific surface area (SSA), and chemical composition as specified by the inductively coupled plasma optical emission spectrometry technique (ICP-OES).

The morphology and structure were investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM).

A degradation test in accordance with norm ISO 10993-4 was conducted.

The developed method enables control of the average grain size and chemical composition of the obtained HAp nanoparticles by regulating the microwave radiation time.

As a consequence, it allows programming of the material degradation rate and makes possible an adjustment of the material activity in a human body to meet individual resorption rate needs.

The authors synthesized a pure, fully crystalline hexagonal hydroxyapatite nanopowder with a specific surface area from 60 to almost 240 m2/g, a Ca/P molar ratio in the range of 1.57–1.67, and an average grain size from 6 nm to over 30 nm.

A 28-day degradation test indicated that the material solubility ranged from 4 to 20 mg/dm3.