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A cathodic-arc evaporation system with plasma-enhanced duct equipment was used to deposit TiZrN, TiZrCN, and TiZr/a-C coatings. Reactive gases (N 2 and C 2 H 2 ) activated by the Ti and Zr plasma in the evaporation process was used to deposit the TiZrCN and TiZr/a-C coatings with different C and nitrogen contents. The crystalline structures and bonding states of coatings were analyzed by X-ray diffraction and X-ray photoelectron spectroscopy. The microbial activity of the coatings was evaluated against Staphylococcus aureus (Gram-positive bacteria) and Actinobacillus actinomycetemcomitans (Gram-negative bacteria) by in vitro antibacterial analysis using a fluorescence staining method employing SYTO9 and a bacterial-viability test on an agar plate. The cell compatibility and morphology related to CCD-966SK cell-line human skin fibroblast cells on the coated samples were also determined using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, reverse-transcriptase-polymerase chain reaction, and scanning electron microscopy. The results suggest that the TiZrCN coatings not only possess better antibacterial performance than TiZrN and TiZr/a-C coatings but also maintain good compatibility with human skin fibroblast cells. [ABSTRACT FROM AUTHOR]

The surface characteristics of biomaterials play an important role in their interaction with biological systems. Tantalum (Ta) oxides and their coatings have been proved to increase their applications in the biomedical fields such as medical devices and dental implants by improving their osseointegration and corrosion resistance. In this study, Ta and amorphous tantalum oxide coatings were deposited by using magnetron sputtering. A hydrophilic crystalline β-Ta 2 O 5 coating was obtained by rapid thermal annealing of the deposited tantalum oxide coating at 700 °C. In this study, Staphylococcus aureus and Actinobacillus actinomycetemcomitans ( A. actinomycetemcomitans ) are Gram-positive and Gram-negative bacteria, respectively, that exhibit physiological commensalism on the human skin and oral areas. Both bacteria were chosen as the model for in vitro anti-bacterial analyses by a fluorescence staining method employing Syto9. The cytocompatibility of human skin fibroblast cells (CCD-966SK) on the coatings was also determined using an MTT assay. It showed that the amorphous tantalum oxide coatings possessed good antibacterial performance, while the hydrophilic crystalline tantalum oxide coatings exhibited outperformed human skin fibroblast cellular biocompatibility. [ABSTRACT FROM AUTHOR]

Pure titanium (Ti) and titanium alloys are widely used as artificial implant materials for biomedical applications. The excellent biocompatibility of Ti has been attributed to the presence of a natural or artificial surface layer of titanium dioxide. Zinc oxide and tantalum oxide thin films are recognized due to their outstanding antibacterial properties. In this study, high power impulse magnetron sputtering (HiPIMS) was used for the deposition of tantalum oxide and zinc-doped Ta(Zn)O thin films on Ti with rough and porous surface, which was pretreated by plasma electrolytic oxidation (PEO). Surface morphology, antibacterial property as well as cell biocompatibility were analyzed. The antibacterial effect was studied individually for the Gram-positive and Gram-negative bacteria Staphylococcus aureus (S. aureus) and Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans). The deposited Ta (Zn)O coating was composed of amorphous tantalum oxide and crystalline ZnO. The antibacterial results on the tantalum oxide and Ta(Zn)O coated Ti indicated a significant inhibition of both S. aureus and A. actinomycetemcomitans bacteria when compared with the uncoated Ti samples. The deposited Ta(Zn)O showed the best antibacterial performance. The Ta(Zn)O coated Ti showed lower level of the cell viability in MG-63 cells compared to other groups, indicating that Zn-doped Ta(Zn)O coatings may restrict the cell viability of hard tissue-derived MG-63 cells. However, the biocompatibility tests demonstrated that the tantalum oxide and Ta(Zn)O coatings improved cell attachment and cell growth in human skin fibroblasts. The cytotoxicity was found similar between the Ta2O5 and Ta(Zn)O coated Ti. By adopting a first PEO surface modification and a subsequent HiPIMS coating deposition, we synthetized amorphous tantalum oxide and Ta(Zn)O coatings that improved titanium surface properties and morphologies, making them a good surface treatment for titanium-based implants. [ABSTRACT FROM AUTHOR]

In this study, amorphous tantalum oxide coatings were deposited onto the Ti substrate with and without plasma electrolytic oxidation (PEO)-pretreatment by using a high-powered impulse magnetron sputtering system. The antibacterial tests were conducted using Syto9 fluorescent dyes to study the antibacterial performance of Gram-positive (Staphylococcus aureus) and Gram-negative (Actinobacillus actinomycetemcomitans) bacteria. In vitro studies, the cell cytotoxicity and cell viability were evaluated with soft-tissue derived human skin fibroblasts and hard-tissue derived human osteosarcoma cells. The results of the antibacterial experiments revealed that both the Ta 2 O 5 and PEO-pretreated Ta 2 O 5 samples had superior antibacterial properties compared to the uncoated Ti samples. Cell viability analyses showed that the Ta 2 O 5 films with and without PEO pretreatment exhibited better cell growth compared to the Ti specimens in human skin fibroblasts and human osteosarcoma cells. The cell viability of PEO-pretreated Ta 2 O 5 films even two-fold higher than the Ti specimens in human osteosarcoma cells. In addition, no cytotoxicity was detected in both the Ta 2 O 5 and PEO-pretreated Ta 2 O 5 films. It concluded that porous Ta 2 O 5 film pretreated with PEO procedure possessed both great biocompatibility and antibacterial abilities. It might have highly potential to be a candidate for the surface materials of dental or orthopedic implants. • Amorphous Ta 2 O 5 are deposited by high-powered impulse magnetron sputtering. • The plasma electrolytic oxidation-pretreated Ta 2 O 5 has the highest hydrophilicity. • The Ta 2 O 5 coatings showed good antibacterial properties. • The cell viability of human skin fibroblasts is the highest for the Ta 2 O 5 coatings. • The MG-63 cell viability is the highest for the porous PEO-pretreated Ta 2 O 5 coatings. [ABSTRACT FROM AUTHOR]