In this article, we present our study of the influence of a graphene oxide (GO) additive and the method of preparation on the properties of membranes. Poly(vinylidene fluoride) (PVDF)/GO membranes were obtained by an inverse phase method, which was conducted by two different methods. The first one was based on solvent evaporation, and the second method was a coagulation bath in distilled water. Our studies clearly showed that the introduction of the GO nanoadditive into the polymer membrane matrix played a major role in the pore process formation, and it also contributed to the reduction of the contact angle, and this led to an improvement in the hydrophilic properties of the obtained membranes. Furthermore, the PVDF/GO membrane preparation process had a direct influence on the thickness and porosity. Both of these factors had a direct influence on the transport properties of the membrane.

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Introduction Oxidative tissue damage caused by reactive oxygen species results in a significant decrease in the total antioxidant capacity of the biological system. The aim of this interdisciplinary study was to answer the question of whether active antioxidants modify, at a molecular and supramolecular level, the tissue of pathological amnion and the necrotic eschar degraded in thermal burn. Methods A Nicolet 6700 Fourier-transform spectrophotometer with OMNIC software and the EasiDiff diffusion accessory were used in the FTIR spectroscopic analysis. A NICOLET MAGNA-IR 860 spectrometer with FT-Raman accessory was used to record the Raman spectra of the samples. The samples were exposed to bacteria capable of causing nosocomial infections, ie Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli and Pseudomonas aeruginosa . Whereas samples of hypotrophic amnion interacted with Staphylococcus aureus, Escherichia coli and Enterococcus faecalis . The obtained flame retardant effect of placentas was evaluated using the method of the limiting oxygen index (LOI). Results The infrared spectroscopy analysis proved that after modification of the amniotic samples in graphene oxide and ortho-silicic acid, the amide II band is split into two components. Incubation of samples in modifier solutions: graphene oxide, sodium ascorbate and L-ascorbic acid results in shifts and changes of intensity within the broadly understood lipid band 1743–1745–1747 cm −1 . The oxidising changes observed within the lipid and amide bands are affected by the incubation effect of graphene oxide as a modifier, possibly adsorbing on the surface of the amniotic membrane. On the basis of microbiological studies, pathogenic bacteria commonly causing amniotic infections and growing in burn wounds were found to have particularly good resistance to stabilized ortho-silicic acid ( E. coli ) and lactoferrin ( S.aureus ). Conclusion This thermogravimetric study found the highest stability of the analysed tissues (hypotrophic amnion and burnt epidermis) after modification with graphene oxide and sodium ascorbate.

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