The broad possibilities of electrochemical impedance spectroscopy for assessing the capacitance of interphase boundaries; the resistance and thickness of the foulant layer were shown by the example of AMX-Sb membrane contacted with red wine from one side and 0.02 M sodium chloride solution from the other side. This enabled us to determine to what extent foulants affect the electrical resistance of ion-exchange membranes, the ohmic resistance and the thickness of diffusion layers, the intensity of water splitting, and the electroconvection in under- and over-limiting current modes. It was established that short-term (10 h) contact of the AMX-Sb membrane with wine reduces the water-splitting due to the screening of fixed groups on the membrane surface by wine components. On the contrary, biofouling, which develops upon a longer membrane operation, enhances water splitting, due to the formation of a bipolar structure on the AMX-Sb surface. This bipolar structure is composed of a positively charged surface of anion-exchange membrane and negatively charged outer membranes of microorganisms. Using optical microscopy and microbiological analysis, it was found that more intense biofouling is observed on the AMX-Sb surface, that has not been in contacted with wine.

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The tissue reaction of pig skin to implantation of decellularized and recellularized dermal matrices on a formed wound defect was evaluated by histological methods on days 2, 5, 8, 16, and 20 after surgery. Differences in tissue response to different matrices were identified. In experimental wounds coated with decellularized dermal matrices, we observed the formation of a scar tissue, which required autodermoplasty on day 12 of the experiment. In wounds coated with recellularized dermal matrices, all layers of the skin completely recovered by day 20 after surgery with the formation of full dermal and epidermal layers. Our findings suggest that reparative morphological changes in the wound depend on the presence of fibroblasts in the implanted dermal matrix.

Despite a significant range of therapeutic measures employed to treat inflammatory diseases in the maxillofacial area, much of the effort falls short of effective suppression of the infection and proper regeneration as the outcome of the pathological process [1-6]. The development of optimal wound covering that would contribute to fast and complete recovery of the damaged structures appears an urgent issue in modern medicine. Scientific items, monographs and patents offer a wide range of materials used to create wound covering, with over 400 various types of sponges, films, combined collagen/gelatin/oxidized cellulose/starch-based implants, etc., described nowadays [7-10]. Of the well-known new-generation biodegradable synthetic and natural materials, a special place A B S T R A C T-A promising area in dentistry is the development of modern biotechnological wound dressings based on chitosan, which, depending on the molecular weight and three-dimensional structure, is able to change its physicomechanical properties from the state of a hydrogel to a dense frame structure with a different degree of swelling, and at the same time perform a depot function the drug introduced into it. Two new types of wound dressings based on chitosan with an immobilized 10% aqueous solution of iodopyrone were developed and their effectiveness was studied in an experiment on animals (rabbits) for dental practice. A comparative analysis was carried out with the well-known wound dressings Alvostaz, Gelatamp by introducing the studied samples into the well of the tooth after its extraction. The high efficiency of the proposed wound dressings based on chitosan was established.