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Institute of Chemistry of Macromolecular Chemistry NAS of Ukraine, 48, Kharkivske shose, Kyiv, 02160, Ukraine Developed polymer composite material with Cefazolin based on polyurethane with isocyanurate fragments (PU), synthesized on the basis of polyoxypropylene glycol (POPG 1000), TDI (2,4;2,6-toluene diisocyanate) and 2,4,6-triisocyanate(trishexamethylene) isocyanate (ICC, Tolonate ™ HDT-LV, MM 1200) at a ratio of NCO: OH = 1: 1 in the medium N,N’-dimethylacetamide (DMAA) and Cefazolin (CFZ). CFZ is immobilized on isocyanurate-containing polyurethane by introducing a solution of CFZ with DMA into the reaction the amount of 5 wt. %. The synthesized polymeric material (PU-CFZ) represents a transparent film of yellow color with physical and mechanical characteristics: σ = 0,15 MPa; ε = 63.40%. According to IR spectroscopy, Cefazolin is immobilized on the polymer matrix by physically due to hydrogen interactions. The influence of biological medium 199 (BM 199) on the structure and properties of PU-CFZ during incubation for 1, 3 and 6 months was studied. It was found that after incubation in BM 199, the structure of PU-CFZ changes as a result of the interaction of enzyme molecules that are part of BM 199 with urethane and amide groups of PU. According to the results of physical and mechanical studies, after incubation in BM 199 for 6 months, PU-CFZ samples are characterized by tensile strength of 0.36 MPa and elongation at break of 98%, ie retain sufficient performance for use in biological objects for up to 6 months. Composite materials with Cefazolin are able to prolong the release of the drug for 28 days in an amount of about 30%, which is sufficient to provide a local therapeutic effect. According to the results of the cytotoxicity study of the developed material by in vitro tissue culture, it was found that the composite material based on isocyanurate-containing polyurethane with Cefazolin is biocompatible.

The study of biodegradation ability of polyurethane foams composite materials with lysozyme under the influence of saline solution for 2 weeks, 1, 3 and 6 months by IR spectroscopy, DSC, TGA was conducted. According to the results of IR spectroscopy under the influence of model medium there are processes of biodegradation, which are confirmed by a decrease in the intensity of the absorption band νС=О. Along with biodegradation there is a redistribution of hydrogen bonds of NH and CO groups of polymer matrix. According to DSC after incubation in saline solution there is an increase in Tg and ΔCp at the glass-transition (for polyurethane foams and composites with lysozyme in the amount of 5 wt. %), an increase in Tg and decrease in ΔCp (for composites with lysozyme in the amount of 1 and 3 wt. %), which indicates the redistribution of hydrogen bonds under the influence of saline solution and due to lysozyme release. It was found that after incubation in saline solution there is an increase in T0 and Tmax for both polyurethane foams and composite materials with lysozyme by the method of TGA. Thus, composites with lysozyme in vitro are heat-resistant materials. According to the study results of the dynamics of lysozyme release composites are capable to the prolonged release of enzyme for 5 days, the amount of which varies depending on the lysozyme content (43.85-61.97 % of the total amount of the introduced drug) and is sufficient for the manifestation of antimicrobial activity. The tissue culture method has established the biocompatibility of investigated materials. For polyurethane foam composite materials with lysozyme more active growth of fibroblastic elements than in the control and polyurethane foam and slowing down the process of cell degeneration was observed. The obtained results indicate that polyurethane foam composite materials with lysozyme are promising materials that due to the presence of the enzyme will have antimicrobial action and can be used in medical practice as polymer composites for the treatment of wounds and burns.