Evgeny Bulanov » Публикация

Аннотация A single-stage innovative method of nano-sized hydroxyapatite Ca5(PO4)3OH (grain size equal 80 nm) synthetizing from aqueous solution was developed. This method is based on interaction between phosphoric acid solution and calcium nitrate in conditions, which are identical to conditions of hydroxyapatite formation in human organism. Structural and thermalphysic investigations of the compound were carried out using methods of high-temperature X-ray diffraction and differential scanning calorimetry. A big isomorphic capacity of apatite structure let us to suggest a number of chemical-modified hydroxyapatite creating ways. These modifications include such substitutions like “phosphorus-silicon”, “calcium-lanthanides”, “hydroxyl-fluorine”. Particularly hydroxyapatite doped by rare-earth elements can be used as an environmentally acceptable luminescent material. Isothermal batch reactor for a commercial production of hydroxyapatite was designed. Optimal conditions for the creating of hydroxyapatite-based bioceramic with controllable volume porosity were selected. Produced ceramic samples can be used in medical techniques for example in bone tissue engineering. Several steps of preclinical test were successfully passed. A new hybrid material which can be represented as high-porous hydroxyapatite ceramic impregnated with degradable polymer (chitosan) was obtained and its strength properties were investigated. For the first time the method of obtaining of hydroxyapatite whiskers (one-dimensioned dislocation-free crystals) using scheme “vapor-liquid-solid” was worked out. These whiskers can be used as a filling compound in composite materials. An improvement of hydroxyapatite sputtering on metallic and ceramic surfaces technique is also one of the most interesting areas of investigations.