ИСТИНА

№ OC-13, 29.11.2024, 11:35 Currently, existing piezoelectric materials have serious disadvantages, primarily because they are non-biodegradable and even toxic, and biocompatible materials have low piezoelectric response values. The aim of this work was to create composite polymer biomaterials with improved piezoelectric response and magnetic properties to study the piezoelectric effect in external magnetic field, and effect of their biodegradation products on the growth of bacteria and mammalian cells. The study of the biocompatibility in vitro and tissue reactions during subcutaneous implantation in vivo enabled the selection of a composite of bacterial PHB with magnetite (Fe3O4) nanoparticles (PHB/M) and with a complex of magnetite and partially reduced graphene oxide (PHB/M-rGO). Microfiber scaffolds were manufactured by electroforming. During the incubation of gram-negative bacteria Escherichia coli in an alternating magnetic field (0.67 Hz, 68 Mt), the adhesion of bacteria on films and scaffolds increased 1.5-2 times, whereas the adhesion of gram-positive bacteria Lactobacillus fermentum was not affected by PHB/M-rGO, and in PHB/M samples, on the contrary, resulted in a 26% decrease. Biodegradation products (nanoparticles of magnetite and its complex with rGO) in an alternating magnetic field reduce the proliferation of rat MSCs, but do not affect the growth of SH-SY5Y. During cells cultivation on films and scaffolds PHB/M and PHB/M-rGO in a low-frequency magnetic field, the proliferation of 3T3-NIH and rat MSCs and the morphology of these cells did not differ. However, in an osteogenic environment the proliferation of MSCs decreased by more than twice and changed their morphology. The proliferation of SH-SY5Y and Hep-2 significantly decreased. Thus, for the first time, we demonstrated the pronounced effect of PHB and its composites with magnetically active nanomaterials, as well as their biodegradation products, on both the adhesion of bacteria of various species and the proliferation of various types of mammalian cells in vitro in the absence of cytotoxicity, which makes the development of various products from these biomaterials promising [1].