In a present paper, we demonstrate novel approach to form ceramic coatings with incorporated ZnO nanoparticles (NPs) on low modulus TiZrNb alloy with enhanced biocompatibility and antibacterial parameters. Plasma Electrolytic Oxidation (PEO) was used to integrate ZnO nanoparticles (average size 12–27 nm), mixed with Ca(H₂PO₂)₂ aqueous solution into low modulus TiZrNb alloy surface. The TiZrNb alloys with integrated ZnO NPs successfully showed higher surface porosity and contact angle. XPS investigations showed presence of Ca ions and absence of phosphate ions in the PEO modified layer, what explains higher values of contact angle. Cell culture experiment (U2OS type) confirmed that the surface of as formed oxide-ZnO NPs demonstrated hydrophobic properties, what can affect primary cell attachment. Further investigations showed that Ca ions in the PEO coating stimulated proliferative activity of attached cells, resulting in competitive adhesion between cells and bacteria in clinical situation. Thus, high contact angle and integrated ZnO NPs prevent bacterial adhesion and considerably enhance the antibacterial property of TiZrNb alloys. A new anodic oxide coating with ZnO NPs could be successfully used for modification of low modulus alloys to decrease post-implantation complications.

Despite the high biocompatibility and clinical effectiveness of Ti-based implants, surface functionalization (with complex osteointegrative/antibacterial strategies) is still required. To enhance the dental implant surface and to provide additional osteoinductive and antibacterial properties, plasma electrolytic oxidation of a pure Ti was performed using a nitrilotriacetic acid (NTA)-based Ag nanoparticles (AgNP)-loaded calcium–phosphate solution. Chemical and structural properties of the surface-modified titanium were assessed using scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) and contact angle measurement. A bacterial adhesion test and cell culture biocompatibility with collagen production were performed to evaluate biological effectiveness of the Ti after the plasma electrolytic process. The NTA-based calcium–phosphate solution with Ag nanoparticles (AgNPs) can provide formation of a thick, porous plasma electrolytic oxidation (PEO) layer enriched in silver oxide. Voltage elevation leads to increased porosity and a hydrophilic nature of the newly formed ceramic coating. The silver-enriched PEO layer exhibits an effective antibacterial effect with high biocompatibility and increased collagen production that could be an effective complex strategy for dental and orthopedic implant development.

The biodegradable metals, including magnesium (Mg), are a convenient alternative to permanent metals but fast uncontrolled corrosion limited wide clinical application. Formation of a barrier coating on Mg alloys could be a successful strategy for the production of a stable external layer that prevents fast corrosion. Our research was aimed to develop an Mg stable oxide coating using plasma electrolytic oxidation (PEO) in silicate-based solutions. 99.9% pure Mg alloy was anodized in electrolytes contained mixtures of sodium silicate and sodium fluoride, calcium hydroxide and sodium hydroxide. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), contact angle (CA), Photoluminescence analysis and immersion tests were performed to assess structural and long-term corrosion properties of the new coating. Biocompatibility and antibacterial potential of the new coating were evaluated using U2OS cell culture and the gram-positive Staphylococcus aureus (S. aureus, strain B 918). PEO provided the formation of a porous oxide layer with relatively high roughness. It was shown that Ca(OH)₂ was a crucial compound for oxidation and surface modification of Mg implants, treated with the PEO method. The addition of Ca²⁺ ions resulted in more intense oxidation of the Mg surface and growth of the oxide layer with a higher active surface area. Cell culture experiments demonstrated appropriate cell adhesion to all investigated coatings with a significantly better proliferation rate for the samples treated in Ca(OH)₂-containing electrolyte. In contrast, NaOH-based electrolyte provided more relevant antibacterial effects but did not support cell proliferation. In conclusion, it should be noted that PEO of Mg alloy in silicate baths containing Ca(OH)₂ provided the formation of stable biocompatible oxide coatings that could be used in the development of commercial degradable implants.

Plasma electrolytic oxidation (PEO) can provide an ideal surface for osteogenic cell attachment and proliferation with further successful osteointegration. However, the same surface is attractive for bacteria due to similar mechanisms of adhesion in prokaryotic and eukaryotic cells. This issue requires the application of additional surface treatments for effective prevention of postoperative infectious complications. In the present work, ZrNb alloy was treated in a Ca-P solution with Ag nanoparticles (AgNPs) for the development of a new oxide layer that hosted osteogenic cells and prevented bacterial adhesion. For the PEO, 0.5 M Ca(H₂PO₂)₂ solution with 264 mg L⁻¹ of round-shaped AgNPs was used. Scanning electron microscopy with energy-dispersive x-ray and x-ray photoelectron spectroscopy were used for morphology and chemical analysis of the obtained samples; the SBF immersion test, bacteria adhesion test, and osteoblast cell culture were used for biological investigation. PEO in a Ca-P bath with AgNPs provides the formation of a mesoporous oxide layer that supports osteoblast cell adhesion and proliferation. Additionally, the obtained surface with incorporated Ag prevents bacterial adhesion in the first 6 h after immersion in a pathogen suspension, which can be an effective approach to prevent infectious complications after implantation.

High strength, excellent corrosion resistance, high biocompatibility, osseointegration ability, and low bacteria adhesion are critical properties of metal implants. Additionally, the implant surface plays a critical role as the cell and bacteria host, and the development of a simultaneously antibacterial and biocompatible implant is still a crucial challenge. Copper nanoparticles (CuNPs) could be a promising alternative to silver in antibacterial surface engineering due to low cell toxicity. In our study, we assessed the biocompatibility and antibacterial properties of a PEO (plasma electrolytic oxidation) coating incorporated with CuNPs (Cu nanoparticles). The structural and chemical parameters of the CuNP and PEO coating were studied with TEM/SEM (Transmission Electron Microscopy/Scanning Electron Microscopy), EDX (Energy-Dispersive X-ray Dpectroscopy), and XRD (X-ray Diffraction) methods. Cell toxicity and bacteria adhesion tests were used to prove the surface safety and antibacterial properties. We can conclude that PEO on a ZrNb alloy in Ca–P solution with CuNPs formed a stable ceramic layer incorporated with Cu nanoparticles. The new surface provided better osteoblast adhesion in all time-points compared with the nontreated metal and showed medium grade antibacterial activities. PEO at 450 V provided better antibacterial properties that are recommended for further investigation.

The study examined the influence of ion-plasma nitriding on the structure, mechanical, and tribological properties of high-speed steels AISI M2 and AISI M41. A comprehensive study was conducted on the changes in phase composition, microhardness, and wear resistance of the obtained modified layers. It was established that the optimal approach was the formation of high-nitrogen martensite without excessive nitrides, which ensured improved mechanical properties of the steels. The dependence of the nitrided layer depth and its microhardness on nitriding temperature and duration was investigated. It was found that at a temperature of 480–520 °C and a processing duration of up to 1 h, a hardened layer with a depth of 25–40 μm was formed, exhibiting increased wear resistance and microhardness of up to 10–12 GPa. The analysis of structural transformations confirmed the presence of ε and γ’ phases, which contributed to increased strength and reduced friction coefficient. The obtained results can be used to improve the technological processes of heat treatment for high-speed steels used in the production of cutting tools. The proposed nitriding parameters contribute to extending the service life of steel components, which is relevant for the mechanical engineering and metallurgical industries.