hydroxyapatite

The study investigates the release of metal nanoparticles (Ag, Cu) or their ionic forms from hydroxyapatite (HA)-based composite materials, which are considered promising antibacterial agents for applications in tissue engineering. The synthesized composites containing silver (AgNPs) and copper (CuNPs) nanoparticles were immersed in Simulated Body Fluid (SBF), a solution that mimics the ionic composition of human blood plasma.

Thermoplastic biodegradable composites based on polyhydroxyalkanoates (PHA) and hydroxyapatite (HA) were obtained by extrusion compounding. It was established that HA influences the crystallinity of PHA, as well as the mechanical and sorption properties of the composites, through its nucleation effect. The key factors determining the ability of PHA to form homogeneous, mechanically stable, and water-resistant composites were identified.

Porous osteoplastic composites using polyhydroxybutyrate as a binder and hydroxyapatite (HA) as a reinforcing component were obtained by press molding. To evaluate the effect of HA particles on the structure and properties of the composites, the amount of filler was varied from 0 to 50 wt%. %. It was found that the addition of HA to the polymer matrix causes a decrease in the mechanical strength of the resulting composites due to the formation of discontinuities in the matrix caused by poor interaction between the matrix and filler particles.

Hydroxyapatite nanoparticles were isolated from a biowaste, buffalo bone, via the thermal decomposition method. The resulting white powdered material was characterized by Fourier Transformed Infrared (FTIR) spectroscopy, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray (EDX) analysis. The FTIR spectra confirmed that a heat treatment of the bone powder at the temperature at or above 1223 K removed the organic moieties leading to the formation of a pure inorganic biomineral.

Usually, in chemical industry the energy of ultrasound is being used to intensify technological processes. However, the complexity of the mechanism of ultrasound action makes it difficult to create a single common theory that could explain its influence on the chemical reactions. Therefore, in each particular case wide-ranging studies of the influence of ultrasound on the chemical reaction, as well as on the structure and properties of the synthesized substances and materials are required.

The polymerization of hydroxylapatite compositions of 2-hydroxyethylmethacrylate with polyvinylpyrrolidone in the presence of silver salts was researched, and it was found that silver salts retard the polymerization velocity. The composites as porous blocks, that containing in their structure silver nanoparticles, were synthesized and their antibacterial and antifunginal properties were confirmed.

Досліджено адгезійні властивості композицій 2-гідроксиетилметакрилату та
полівінідпіролідоном за різних ініціювальних систем. Проаналізовано вплив різної
природи ініціатора полімеризації на адгезійну міцність клейового шару, утвореного з
композицій з мінеральних наповнювачів. Використано наповнювачі з різними фізико-
хімічними, структурними та іншими властивостями, а саме: гідроксиапатит, монтмо-
рилоніт та комплекс монтморилоніт – полівінілпіролідон (1:5). Встановлено вплив

The influence of nature and mineral filler amount on adhesive ability of composite materials based on 2-hydroxyethylmethacrylate and polyvinylpyrrolidone modified by the low-molecular additives has been determined. The hydroxyapatite effect on the value of adhesive strength of the glued seam composites has been researched.

The polymerization of 2-hydroxyethylmethacrylate compositions with polyvinylpyrrolidone has been investigated in the presence of mineral fillers (hydroxyapatite, montmorillonite and wollastonite). The influence of the nature and amount of mineral filler on polymerization kinetics and composition of copolymers has been determined. In the composite structure silver particles were obtained via silver nitrate reduction by polyvinylpyrrolidone tertiary nitrogen. The synthesized silver-containing composites possess bactericidal properties against E. colі and S. aureus bacteria, in particular.