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Introduction reflects the great interest of practical restorative medicine in artificial structures that mimic the structure and properties of natural bone tissue that are made from biocompatible composite materials suitable for restoring the integrity of bone elements of the musculoskeletal system. The Introduction also contains the physicochemical foundations and approaches to a new ultrasonic technologies providing accelerated production of a biocompatible composite material, precisely hydroxyapatite particles in a collagen matrix. Experimental part contains a description of methods and equipmets for accelerated production of a hydroxyapatite suspension in the field of a hydroacoustic emitter, which ensures that the cavitation threshold at room temperature is exceeded, at which intense acoustic vortex microflows provide a decrease in diffusion restrictions, accelerating the interaction between reacting components. The reaction is carried out with the simultaneous supply of an aqueous solution of calcium monophosphate hydrate and a suspension of calcium hydroxide. The resulting finished product is separated using an ultrasonic self-cleaning filter, where the same, by nature, microflows allow the implementation of a continuous accelerated separation of synthesized particles in an ultrasonic self-cleaning filter of the installation, where, after separation, the precipitate is also subjected to cleaning. The resulting particles of hydroxyapatite mixed with the solution collagen and homogenized in an ultrasonic field at frequency of 22 kHz and an energy density in the reaction volume from 1 to 10 W / cm3. Obtained homogenate can be easily used to create various implant designs with predetermined sizes and shapes and after freezedrying was transformed in biocompatible composite with a porous structure. To control biocompatibility, samples of this composite in form of thin plate was sewed under the skin into the scruff of white lab rats. A suspension of hydroxyapatite mechanically combined with the collagen during 30 s homogenization by ultrasound at frequency of 22 kHz and at energy density of 3 W / cm3, form a complex that is freeze-dried, after which it can be used to form the biocomposite body with porous structure and with given dimensions and shapes. Subcutaneous implantation of plates of a calcium-phosphate biocomposite with a biodegradable polymer collagen, into the scruff of a laboratory white mouse showed its good biocompatibility with tissues of a living organism, without causing either immediate or delayed adverse events in them.

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Crystallization of antibiotics and other biologically active substances from water solutions represents an important stage of their biotechnological production. The process is based on a sharp reduction of a target compound solubility caused by either temperature decrease, or supersaturation of a solution. A preconditioning of a solution, i.e., its evaporation with a simultaneous temperature decrease seems to be an optimal technical solution, especially advantageous for the treatment of thermolabile substances. This paper describes the technology and equipment for the pre-crystallization treatment of solutions of various substances produced by the biotechnological and chemical industries. The proposed preconditioning technology includes ultrasonic dispersion of a solution and formation of an aerosol with a large integral evaporation surface followed by condensation. Comparing to common tubular evaporators used in various industrial processes, this technology provides about equal productivity and, at the same time, lower energy consumption, since it does not require the heating and the further cooling of a solution needed to evaporate and condensate the solvent, respectively, that prevents undesirable effect of high temperature on thermolabile compounds. In addition, the technology prevents the damage of thermolabile compounds, improves the efficiency of the further crystallization process due to the ultrasound-stimulated formation of crystallizing nuclei, and provides a solvent distillate suitable for the further re-use. The designed device for preconditioning has been successfully tested using culture broth of Streptomyces sp. containing a feed antibiotic virginiamycin; such treatment with the further crystallization in standard crystallizers has resulted in the efficient formation of equal-sized antibiotic crystals.