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Nanopowders of hydroxyapatite (HA), modified by magnesium (MgHA) and by silicon (SiHA) were obtained by liquid-phase microwave synthesis method. X-ray diffraction and IR spectroscopy results showed that Mg2+ and SiO44− ions were present in the synthesized products both as secondary phases and as part of the HA phase. Whitlockite was found in the magnesium-modified HA (MgHA) and larnite was found in the silicon-modified HA (SiHA); ion substitution for both materials resulted in solid solutions. In the synthesized samples of modified HA, the increase of particle size of powders was in the order HA 2+, Mg2+, Si4+) were present using spectral probes on the surface of the samples of HA, MgHA, and SiHA, and the acidity of these sites decreased in the order SiHA > MgHA > HA. The rates of calcium phosphate layer deposition on the surface of these materials at 37 °C in the model simulated body fluid solution showed similar dependence.

Relevance of the work is due to the need for new materials that are used in medicine as a substitute for natural bone tissue injuries, fractures, etc. The aim of the work is to obtain composites with improved biocompatible properties based on poly-L-lactide (PLA) and hydroxyapatite (HA) and to perform pilot analysis of interaction PLA, HA, composite PLA-HA with primary human monocytes-derived macrophages in vitro. The pilot experiments using human primary monocytes cultivated on the surface of the samples demonstrated that PLA-HA can stimulate release of anti-inflammatory cytokines that indicates the presence of potential anti-inflammatory properties of the composites

Composites based on lactic acid oligomers, calcium hydrophosphate and hydroxyapatite synthesized under the action of microwave radiation were obtained in situ. The appearance of a new band associated with stretching vibrations of >C=O in spectra of the chloroform-insoluble fraction is indicative of the chemical interaction between lactic acid and hydroxyapatite. To determine whether a calcium phosphate layer can be formed on the surface of composite samples, biomimetic studies in a physiological SBF solution were carried out during 28 days at 37°C. It was found that all samples containing calcium phosphates promote active formation of a new calcium phosphate layer, whereas lactic acid oligomer in samples containing no inorganic component undergoes destruction in the SBF solution as a result of hydrolysis. The estimate of the resorption rate demonstrated that the solubility of calcium phosphates contained in the composites at 20°C in the physiological solution is 3–7 times that of pure hydroxyapatite.

Method for microwave liquid-phase synthesis of hydroxyapatite samples was developed. The composition of the synthesis products obtained and natural hydroxyapatite was studied by X-ray phase and X-ray fluorescence microanalysis. IR spectra were measured and the dispersity of hydroxyapatite powders obtained, their solubility in water at 20°C, and structural parameters were determined in comparison with natural hydroxyapatite and that produced by the common (“classical”) liquid-phase technique. The microwave-synthesized hydroxyapatite compares well in its properties with the biological and “classical” hydroxyapatites.

The effect of silver adding to hydroxyapatite (HA) in its solubility in physiological solution and biological activity was investigated. Samples of HA containing silver (AgHA) obtained by liquid-phase method in the conditions of microwave exposure. Solubility (CCa2+·103, mol/l) of the powders AgHA was determined by chemical methods according trilonometric titration of the calcium ions in physiological solution at 25 and 37 °C. To investigate the biological activity of the samples, a series of experiments on the formation of the calcium-phosphate layer on the surface of the SBF-solution at 37 °C for 28 days. Electronic micrographs of samples taken at the end of each 7 days of the experiment, indicate the formation of calcium-phosphate layer (CPL) in the samples, the kinetics of which is shown as a function of cumulative concentrations of calcium and magnesium ions from time.

Relevance of the work is due to the need for new materials that are used in medicine (orthopedics, surgery, dentistry, and others) as a substitute for natural bone tissue injuries, fractures, etc. The aim of presented work is developing of a method of producing biocompatible materials based on polyesters of hydroxycarboxylic acids and calcium phosphate ceramic (hydroxyapatite, HA) with homogeneous distribution of the inorganic component. Bioactive composites based on poly-L-lactide (PL) and hydroxyapatite with homogeneous distribution were prepared. The results of scanning electron microscopy confirm homogeneous distribution of the inorganic filler in the polymer matrix. The positive effect of ultrasound on the homogeneity of the composites was determined. The rate of hydrolysis of composites was evaluated. The rate of hydrolysis of polylactide as an individual substance is 7 times lower than the rate of hydrolysis of the polylactide as a part of the composite. It was found that materials submarines HA composite and do not cause a negative response in the cells of the immune system, while contributing to anti-inflammatory cytokines released by cells.