A high-hydrophilic Cu2O-TiO2/Ti2O3/TiO coating on Ti-5Cu alloy: Perfect antibacterial property and rapid endothelialization potential.

In order to make novel antibacterial Ti-Cu alloy more suitable for cardiovascular implant application, a Cu-containing oxide coating was manufactured on Ti-Cu alloy by plasma-enhanced oxidation deposition in plasma enhanced chemical vapor deposition (PECVD) equipment to further improve the antibacterial ability and the surface bioactivity. The results of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and water contact angle indicated that a sustainably high-hydrophilic Cu2O-TiO2/Ti2O3/TiO coating with nano-morphology on Ti-5Cu was successfully constructed. The corrosion performance results showed that the coating enhanced the corrosion resistance while releasing more Cu2+, compared with Ti-5Cu. Antibacterial tests confirmed the perfect antibacterial property of the coating (R ≥ 99.9 %), superior to Ti-Cu alloy (R > 90 %). More delightfully, it was observed by phalloidin-FITC and DAPI staining that the coating improved the early adhesion of HUVEC cells mainly due to strong hydrophilicity and nano-morphology. It was demonstrated that the extract of the coated sample significantly promoted proliferation (RGR = 112 %-138 % after cultivation for 1 to 3 days) and migration of HUVEC cells due to the appropriate Cu2+ release concentration. Hemolysis assay and platelet adhesion results showed that the coating had excellent blood compatibility. All results suggested that the coating on Ti-Cu alloy might be a promising surface with the perfect antibacterial ability, blood compatibility and evident promoting endothelialization ability for the cardiovascular application.

Development of a low elastic modulus and antibacterial Ti-13Nb-13Zr-5Cu titanium alloy by microstructure controlling.

In order to prepare a titanium with a low elastic modulus and good antibacterial property to meet the requirements as a biomedical material, Ti-13Nb-13Zr-5Cu (TNZ-5Cu) alloy was prepared by high vacuum consume electric arc melting furnace and then subjected to a solution treatment at 950 °C followed by a short-term aging treatment at 600 °C, for 15 min, 30 min, 1 h and 2 h, respectively. The microstructure, mechanical property, antibacterial property and biocompatibility of TNZ-5Cu were investigated in detail. The research results have shown that the solid solution treated alloy was mainly composed of ß-phase and α″-phase, while the aged alloys of ß-phase, α″-phase, α-phase and Ti2Cu. Compared with Ti-13Nb-13Zr alloy (65 GPa) and Ti-6Al-4 V alloy (111 GPa), the elastic modulus of TNZ-5Cu alloy after solution treatment was about 72 GPa and increased with the aging treatment up to 85 GPa, and the hardness was maintained at a higher level than that of Ti-13Nb-13Zr alloys (288 HV). The bacteria plate count results showed that the antibacterial ability of TNZ-5Cu alloy increased with the extension of the aging duration from <60% at 15-30 min to >90% at 1-2 h. Cell experiments showed that all TNZ-5Cu alloy had good cell compatibility. The low modulus and the antibacterial property could provide potential to avoid stress shield and device-related inflection in the clinical application.