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This work deals with the problem of synthesis and investigation of the structure and properties of polymer calcium phosphate biopolymer suspensions, their use to obtain film samples containing drugs, and the study of the kinetics of drug release from the polymer matrix. The compositions were synthesized using the method of mechano-acoustic activation. The use of the mechano-acoustic activation technique and ultrasonic dispersion makes it possible to synthesize calcium phosphate compounds in aqueous media, to modify the synthesized products with drugs and bioactive substances, and to form biocompositions for the manufacture of bone implants.

Работа посвящена проблеме синтеза и изучения структуры и свойств полимерных кальций-фосфатных биополимерных суспензий, получению на их основе пленочных образцов с лекарственными веществами и изучению кинетики их высвобождения из полимерной матрицы. Синтез композиций осуществляли с помощью метода механоакустической активации. Применение техники механоакустической активации, ультразвукового диспергирования позволяют проводить синтез кальций-фосфатных соединений в водных средах и модифицировать синтезированные продукты лекарствами, биоактивными веществами и формировать биокомпозиции для изготовления костных имплантатов. Ключевые слова: механоакустическая активация, кальций-фосфатные соединения, биополимерные композиты, гидроксиапатит, порфирины.

Hydroxyapatite was synthesized in conditions of mechanoacoustic treatment of an aqueous reaction mixture consisting of ammonium hydrogen phosphate and calcium nitrate using a commercially available rotary pulsation apparatus. Mechanoacoustic treatment of the reaction mixture was found to lead to the formation of nanosized hydroxyapatite particles with a predominant mean diameter of about 20 nm. Purification of technical hydroxyapatite to remove traces of ammonium nitrate by thermal processing at 350°C is proposed. The crystalline phase of hydroxyapatite was found not to be dominant in the structure. The porosity of hydroxyapatite amounted to about 75% with a mean pore diameter of 2.8 × 103 nm. Thermal processing of hydroxyapatite in aqueous medium was found to yield a paste-like form. Hydroxyapatite paste had no cytotoxicity and did not prevent cell adhesion, though it almost completely inhibited cell spreading.

An organo-mineral composite bone-grafting material was developed and tested. The composite material is based on synthetic hydroxyapatite (HAP) (30-60 wt%) integrated into the matrix of poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogel. The composite was shown to have a homogeneous and isotropic microstructure, mechanical strength of ~11 MPa, high degree of water absorption reaching 34%, and elastomeric properties under physio-logical conditions (strain at failure is 57%).

New technological approaches based on biocompatible nanocomposites with hydroxyapatite (HA) and collagen matrix are described. Optimal conditions of HA synthesis in collagen fibers and its use in bone implants are discussed.

Wood residue crumbling with a rotary-pulse device is considered. Structural analysis of the resulting materials is carried out.