The characterization of the microstructure, morphology, topography, composition, and physical and chemical properties of the coatings containing β-tricalcium phosphate (β-TCP) particles deposited by the micro-arc oxidation (MAO) method on biodegradable Mg-0.8Ca alloy has been performed. The electrolyte for the MAO process included the following components: Na₂HPO₄·12H₂O, NaOH, NaF, and β-Ca₃(PO₄)₂ (β-TCP). The coating morphology, microstructure, and compositions have been studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). With increasing of the MAO voltage from 350 to 500 V, the coating thickness and surface average roughness of the coatings increased linearly from 6 to 150 µm and from 2 to 8 µm, respectively. The coating deposited at 350 V had more homogeneous porous morphology with numerous pores similar by sizes (2–3 µm) than the coatings formed at 450–500 V. The β-TCP isometric particles were included in the coating surface. The XRD recognized the amorphous-crystalline structure in the coatings with incorporation of the following phases: β-TCP, α-TCP, MgO (periclase) and hydroxyapatite (HA). The corrosion experiments showed that the biodegradation rate of the Mg-0.8Ca alloy coated by calcium phosphates is almost 10 times less than that of uncoated alloy.

Zn-doped and Cu-doped SiO_x films were synthesized by atmospheric pressure plasma chemical vapor deposition to study their antibacterial efficiency against Gram-negative Escherichia coli and their cytotoxic effect on the growth of mouse cells. Zn-rich and Cu-rich particles with diameters up to several microns were found to be homogeneously distributed within the SiO_x films. For both doping elements, bacteria are killed within the first three hours after exposure to the film surface. In contrast, mouse cells grow well on the surfaces of both film types, with a slight inhibition present only after the first day of exposure. The obtained results indicate that the films show a high potential for use as effective antibacterial surfaces for medical applications.

A comparative analysis of the structure, properties and the corrosion behavior of the micro-arc coatings based on Sr-substituted hydroxyapatite (Sr-HA) and Sr-substituted tricalcium phosphate (Sr-TCP) deposited on Mg0.8Ca alloy substrates was performed. The current density during the formation of the Sr-HA coatings was higher than that for the Sr-TCP coatings. As a result, the Sr-HA coatings were thicker and had a greater surface roughness R_a than the Sr-TCP coatings. In addition, pore sizes of the Sr-HA were almost two times larger. The ratio (Ca + Sr + Mg)/P were equal 1.64 and 1.47 for Sr-HA and Sr-TCP coatings, respectively. Thus, it can be assumed that the composition of Sr-HA and Sr-TCP coatings was predominantly presented by (Sr,Mg)-substituted hydroxyapatite and (Sr,Mg)-substituted tricalcium phosphate. However, the average content of Sr was approximately the same for both types of the coatings and was equal to 1.8 at.%. The Sr-HA coatings were less soluble and had higher corrosion resistance than the Sr-TCP coatings. Cytotoxic tests in vitro demonstrated a higher cell viability after cultivation with extracts of the Sr-HA coatings.

Biodegradable materials are currently attracting the attention of scientists as materials for implants in reconstructive medicine. At the same time, ceramics based on calcium silicates are promising materials for bone recovery, because Ca²⁺ and Si²⁺ ions are necessary for the mineralization process, and they take an active part in the formation of apatite. In the presented research, the protective silicate biocoatings on a Mg0.8Ca alloy were formed by means of the micro-arc oxidation method, and the study of their morphology, structure, phase composition, corrosion, and biological properties was carried out. Elongated crystals and pores were uniformly distributed over the surface of the coatings. The coated samples exhibited remarkable anti-corrosion properties in comparison with bare magnesium alloy because their corrosion current decreased 10 times, and their corrosion resistance increased almost 100 times. The coatings did not significantly affect the viability of the cells, even without the additional dilution of the extract, and were non-toxic according to ISO 10993-5: 2009. In this case, there was a significant difference in toxicity of the pure Mg0.8Ca alloy and the coated samples. Thus, the results demonstrated that the applied coatings significantly reduced the toxicity of the alloy.

Chronic inflammation leading to implant failure present major challenges in orthopedics, dentistry, and reconstructive surgery. Titanium alloys, while widely used, often provoke inflammatory complications. Zinc-doped calcium phosphate (CaP) coatings offer potential to enhance implant integration by improving corrosion resistance, bioactivity, and immunocompatibility. The objective of the study was to develope novel coating composition based on zinc-doped CaP coatings on Ti64 alloy implants that for the first time combines improved corrosion resistance, antibacterial properties and principally improved compatibly with the innate immunity primarily due to the proper programming of resident tissue macrophages to promote long-term implant acceptance. Ti64 substrates were coated with CaP and Zn-doped CaP using the microarc oxidation (MAO) technique. The adhesion between substrate and coatings are investigated by the progressive scratch test. The corrosion resistance and bioactivity were evaluated through electrochemical tests and simulated body fluid immersion. RNA sequencing was used to assess inflammatory responses in human primary macrophages. Antibacterial efficacy was tested against Escherichia coli and Staphylococcus aureus. Zn addition significantly increased the adhesion of the coatings to Ti64 alloy, doubling up the critical load (from 4 N to 11 N). Zn-doped CaP coatings demonstrated enhanced corrosion resistance and increased biomineralization. RNA sequencing revealed that Zn addition suppressed inflammatory and promoted tolerogenic macrophage programming. Most pronounced effects was compensatory effect Zi on the CaP-supressed oxidative phosphorylation and lysosomal pathways in healing macrophages, and by upregulation of metallothioneins. Zn-doped coatings also exhibited superior antibacterial efficacy, reducing E. coli and S. aureus colonization by 99 % and 90 %, respectively. Zinc-doped CaP coatings on Ti64 implants significantly improved corrosion resistance, bioactivity, and antibacterial performance. We developed advanced multifunctional biomaterial equipped with beneficial anti-inflammatory and tissue integrative programming of innate immunity providing principal advantages for the long-term implant integration and reducing the implant failure risks.