There is a growing interest in the utilization of metal oxide nanoparticles as antimicrobial agents. This review will focus on titanium dioxide nanoparticles (TiO₂ NPs), which have been demonstrated to exhibit high antimicrobial activity against bacteria and fungi, chemical stability, low toxicity to eukaryotic cells, and therefore high biocompatibility. Despite the extensive research conducted in this field, there is currently no consensus on how to enhance the antimicrobial efficacy of TiO₂ NPs. The aim of this review is to evaluate the influence of various factors, including particle size, shape, composition, and synthesis parameters, as well as microbial type, on the antibacterial activity of TiO₂ NPs against bacteria and fungi. Furthermore, the review offers a comprehensive overview of the methodologies employed in the synthesis and characterization of TiO₂ NPs. The antimicrobial activity of TiO₂ exhibits a weak dependence on the microorganism species. A tendency towards increased antibacterial activity is observed with decreasing TiO₂ NP size. The dependence on the shape and composition is more pronounced. The most pronounced antimicrobial potential is exhibited by amorphous NPs and NPs doped with inorganic compounds. This review may be of interest to specialists in biology, medicine, chemistry, and other related fields.

New materials for additive manufacturing are currently being actively studied, which both have the necessary physicochemical properties and are safe for the environment and living organisms. We have proposed a simple process for the production of composite materials based on a transparent polymethyl methacrylate-like photopolymer resin modified with metallic titanium nanoparticles. Standardized plate samples were printed from the obtained modified photopolymer resins using mask stereolithography with an LED light source array (MSLA), and their mechanical properties were evaluated. Plates were also printed, for which the surface topology, distribution of nanoparticles in the polymer matrix, chemical structure, optical properties, chemical structure, and optical properties were characterized. In the context of the impact on biological systems, the ability of materials to enhance the formation of ROS and affect the main biomacromolecules was demonstrated. At the same time, the developed composite materials inhibit the growth of E. coli bacterial cells, and the bactericidal effect of the surfaces of the obtained materials was shown. Despite the significant antibacterial properties of the synthesized materials, no negative impact on the growth and development of adhesive cultures of eukaryotic cells in vitro was detected.

In various areas of human activity, there is a need for new antimicrobial agents that are minimally hazardous to humans and the environment while remaining effective against multidrug-resistant microorganisms. The use of nanomaterials, particularly carbon-based ones, for this purpose is attracting growing interest. This review presents a quantitative analysis, based on published data, of the antibacterial and antifungal activity of various carbon nanomaterials, focusing on fullerenes, nanodiamonds, graphene oxide, carbon nanotubes, and carbon dots. Their antimicrobial activity is compared both among themselves and with other antimicrobial agents; the effects of their physicochemical properties, functionalization, and photodynamic activity on this activity are also examined.

In this paper, titanium oxide nanoparticles (TiO₂-NPs) with complex surface topologies were obtained for the first time using simple procedures applied in laser sintering. Based on the obtained nanoparticles and polymethyl methacrylate-like photopolymer resin, a composite material (MPR/TiO₂-NPs) for 3D printing was created using the MSLA technology. Products made of the material containing from 0.001 to 0.1% wt. TiO₂-NPs didn’t contain internal defects and were less brittle than the resin without nanoparticles. Products made of the MPR/TiO₂-NPs material were well polished; after polishing, areas with a variation in the surface profile height of less than 10 nm were found on the surfaces. Nanoparticles in the volume of products made of the material are apparently unevenly distributed; there are alternating areas of micrometer sizes with slightly higher and slightly lower concentrations of nanoparticles. Spectroscopy showed that adding the developed nanoparticles promoted better polymerization of the MPR resin. The addition of nanoparticles to the material slightly increased its ability to generate active forms of oxygen and damage biomacromolecules. At the same time, the resulting material exhibits significant antibacterial properties and doen’t affect the growth and reproduction of animal cells. The created material can be a very effective basis for the additive manufacturing of products with improved physical and chemical properties and balanced biological activity.

Methacrylate photopolymer resin (MPR) is widely used in various fields, including the biomedical field. There are several problems associated with their use: the potential toxicity of monomer residues during incomplete polymerization and the possibility of bacterial expansion. Doping polymers with nanoparticles is one of the ways to increase the degree of polymerization (protection from toxicity), improve the performance characteristics of the polymer, and add antibacterial properties. We used an in situ polymerization method to obtain the composites of MPR with tellurium nanoparticles (TeNPs) with a dopant concentration of 0.001, 0.01, or 0.1% (v/v). The composite of MPR+TeNPs had a higher degree of polymerization compared to MPR without NPs, improved mechanical properties, and pronounced antibacterial activity. The effects depended on the concentration of TeNPs. All of the studied composites had no cytotoxic effect on human cells. MPR+TeNPs 0.1% had the maximum antibacterial effect, which is probably realized through Te-dependent induction of oxidative stress (increase in the generation of 9-oxoguanine and long-lived reactive forms of proteins). The results obtained deepen the knowledge about the influence of NPs of leading metals on photopolymerization and the final properties of the methacrylate matrix, and the synthesized MPR+TeNP composites may find potential biomedical applications in the future.

Silicon dioxide (SiO₂) nanoparticles approximately 5 nm in size have been obtained. A method has been developed for introducing SiO₂ nanoparticles into photolithographic resin at concentrations up to 0.1%. Composite resins can be used to manufacture parts with complex geometries with a maximum achievable resolution of 50 μm. Parts made from composite resin with SiO₂ nanoparticles polish well. After polishing, areas of approximately 100 μm² with height differences of less than 10 nm are revealed on the surface of the parts. A relatively uniform distribution of SiO₂ nanoparticles is observed within the parts, and no optical defects are detected. However, areas differing in the phase shift of electromagnetic radiation are observed within the parts. Importantly, the presence of nanoparticles in the resin during MSLA printing increases the degree of resin polymerization. SiO₂ nanoparticles have been shown to have prooxidant properties, leading to the formation of 8-oxoguanine in DNA and long-lived reactive protein species. Components made from photolithographic resins with SiO₂ nanoparticles have been shown to inhibit the growth and development of E. coli bacteria, with a significant loss of viability. Despite their antimicrobial properties, components made from photolithographic resins with SiO₂ nanoparticles do not affect the growth and development of mammalian cells.