A soft synthesis of nanoceria with non-stoichiometric composition (33% Ce³⁺/67% Ce⁴⁺) named CeO₂ NPs in bacterial cellulose (BC) matrix in the form of aerogel and hydrogel with controlled CeO₂ NPs content was proposed. The advantage of CeO₂ NPs synthesis in BC is the use of systemic antacid API–trisamine as a precursor, which did not destruct cellulose at room temperature and enabled a reduction in the duration of synthesis and the number of washes. Moreover, this method resulted in the subsequent uniform distribution of CeO₂ NPs in the BC matrix due to cerium (III) nitrate sorption in the BC matrix. CeO₂ NPs (0.1–50.0%) in the BC matrix had a fluorite structure with a size of 3–5 nm; the specific surface area of the composites was 233.728 m²/g. CeO₂ NPs in the BC-CeO₂ NPs composite demonstrated SOD-like activity in the processes of oxidation and reduction of cytochrome c (cyt c³⁺/cyt c²⁺), as well as epinephrine to inhibit its auto-oxidation in aqueous solutions by 33–63% relative to the control. In vitro experiments on rat blood showed a decrease in the MDA level and an increase in the activity of antioxidant defense enzymes–SOD by 24% and G6PDH by 2.0–2.5 times. Therefore, BC-CeO₂ NPs can be proposed for wound healing as antioxidant material.

The synthesis of two new copolymer conjugates of methoxyoligo(ethylene glycol)methacrylate MPEGMA and betulin methacrylate BM was developed via RAFT polymerization. The molar content of BM units was equal to 9–10 and 13–16 mol%, respectively (HPLC, ¹H and ¹³C NMR); molar weights were equal to 75000–115000. CeO₂ NPs as a component of the hybrid material were synthesized for the preparation of the composition with copolymer conjugates of MPEGMA and BM. We showed a significant increase in G6PDH and GR activities by 21–51% and 9–132%, respectively, which was due to the increase in NADPH concentration under the action of copolymers in vitro. The actions of copolymers and CeO₂ NPs combination were stronger than those of the individual components: the SOD activity increased by more than 30%, the catalase activity increased dose-dependently from 13 to 45%, and the GR activity increased to 49%. The maximum increase in enzyme activity was observed for the G6PDH from 54% to 151%. The MDA level dose-dependently increased by 3–15% under the action of copolymers compared with the control, and dose-dependently decreased by 3–12% in samples containing CeO₂ NPs only. CeO₂ NP–copolymer compositions can be used for the design of new biomimetic medical products with controlled antioxidant properties.

New approach is described to synthesis of biomimetic materials on the basis of hydroxyapatite particles and collagen suspension produced from fish-production wastes. A simultaneous joint in vitro...