Microwave treatment and pH influence on hydroxyapatite morphology and structure

This paper reports the influence of microwave treatment duration and pH conditions of initial precursors on the morphological and crystalline dispersity of the hydroxyapatite (HAp) synthesized by hydrothermal method.The obtained HAp samples were studied by scanning electron microscopy, X-Ray diffraction method and low nitrogen adsorption method. We have obtained nanostructured crystalline hydroxyapatite with 95% crystallinity, porous structure and average particles size in interval 17...46 nm consolidated in aggregates with size distribution of 0.5...25 μm. The pH growth from 8 to 13 results in double increase of HAp specific area(from 69 up to 133 m²/g), meanwhile microwave irradiation brings to particles aggregation: HAp treated during 0... 10...30 min have specific surface are 112...67...41 m²/g, respectively. As a result at pH=13 and without microwave irradiation treatment we synthesized HAp with maximum surface compared to the surface of natural HAp that makes obtained HApto be promising material in biotechnological applications.