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Highlights: [•] Zn was implanted into titanium using plasma immersion ion implantation technology. [•] The Zn-implanted titanium surfaces exhibited excellent osteogenic activity. [•] The Zn-implanted titanium surfaces possessed partly antibacterial effect. [Copyright &y& Elsevier]

Graphical abstract Highlights • Partially fluorinated graphene shows favorable antibacterial ability. • Fluorinated graphene film could inhibit platelet aggregation. • Partially fluorinated graphene is more suitable for biological applications. Abstract Graphene halides are promising two-dimensional systems which have interesting physical and chemical properties. In particular, high quality fluorinated graphene offers a great potential in modulating variable properties by regulating its surface microstructure. Moreover, the fluorine introduction and carbon-fluorine bonding characters will enable some interesting biological response. Here, the biological responses to bacteria and cells of fluorinated graphene were studied. Present work revealed that partially fluorinated graphene behaved satisfactory antibacterial ability. Fluorinated graphene showed well facilitating function to cell adhesion in early period, however, after a longer incubation period, the enhanced intracellular ROS level in rBMSCs on the fully fluorinated graphene gives rise to the decrease of cell viability. It was found that there is no statistical difference in the activity of alkaline phosphatase (ALP) and matrix mineralization of rBMSCs on pristine graphene, partially fluorinated graphene and fluorographene. In addition, the introduction of fluorine into pristine graphene plane reduced the adhesion and aggregation of blood platelets due to the attenuation of π–π interaction between material surface and blood protein. The findings in this work revealed that partial fluorinated graphene exhibited better antibacterial ability and cytocompatibility, outperforming pristine graphene and fluorographene. [ABSTRACT FROM AUTHOR]

Titanium (Ti) has been widely used as orthopedic and dental implants, it is very important to improve the osteogenic activity and antibacterial ability of titanium implants. The objective of this work was to investigate the osteogenic and antibacterial ability of the zinc (Zn) ion implanted Ti at different implantation voltage. X-ray photoelectron spectroscopy results indicate that Zn was successfully implanted into titanium. Zn-implanted titanium surfaces exhibit enhanced cell proliferation ability, alkaline phosphatase (ALP) activity, and partial resistance to both Escherichia coli ( E . coli ) and Staphylococcus aureus ( S . aureus ). The excellent osteogenic and antibacterial ability are highly related to the implantation voltage. The cell proliferation and antibacterial ability can be enhanced by increasing the implantation voltage from 15 kV to 30 kV, indicating that Zn implantation at 30 kV is more beneficial to both osteogenic and antibacterial ability. [ABSTRACT FROM AUTHOR]

Titanium implants possessing simultaneous osseointegration and antibacterial ability are desirable. In this work, three types of Zn/Ag micro-galvanic couples are fabricated on titanium by plasma immersion ion implantation to investigate the osseointegration and antibacterial effects as well as the involved mechanisms. The in vitro findings disclose enhanced proliferation, osteogenic differentiation, and gene expressions of the rat bone mesenchymal stem cells (rBMSCs), as well as good antibacterial ability on all three micro-galvanic couples. Excellent antimicrobial ability is also observed in vivo and the micro-CT and histological results reveal notable osseointegration in vivo despite the presence of bacteria. The Zn/Ag micro-galvanic couple formed on Zn/Ag dual-ion co-implanted titanium shows the best osseointegration as well as good antibacterial properties in vivo obtained from a rabbit tibia model. The difference among the three Zn/Ag micro-galvanic couples can be ascribed to the contact between the Ag NPs and Zn film, which affects the corrosion process. Our results indicate that the biological behavior can be controlled by the corrosion process of the Zn/Ag micro-galvanic couples. [ABSTRACT FROM AUTHOR]

Abstract: Zinc (Zn) and silver (Ag) are co-implanted into titanium by plasma immersion ion implantation. A Zn containing film with Ag nanoparticles (Ag NPs) possessing a wide size distribution is formed on the surface and the corrosion resistance is improved due to the micro-galvanic couples formed by the implanted Zn and Ag. Not only are the initial adhesion, spreading, proliferation and osteogenic differentiation of rBMSCs observed from the Zn/Ag implanted Ti in vitro, but also bacteria killing is achieved both in vitro and in vivo. Electrochemical polarization and ion release measurements suggest that the excellent osteogenic activity and antibacterial ability of the Zn/Ag co-implanted titanium are related to the synergistic effect resulting from the long-range interactions of the released Zn ions and short-range interactions of the embedded Ag NPs. The Zn/Ag co-implanted titanium offers both excellent osteogenic activity and antibacterial ability and has large potential in orthopedic and dental implants. [Copyright &y& Elsevier]

Abstract With the ability to host anions or neutral drugs, layered double hydroxide (LDH) are hot spots in the field of biomaterials. Intensive works so far only have focused on their application in surface modification or injectable medicine. Yet, little literatures report the potential of LDH as bone implants. In the present study, four types of LDH (Mg Al, Mg Fe, Zn Al and Zn Fe) were prepared via a coprecipitation method. Our results showed that the synthetic LDH powders can be pressed into discs in the absence of binder. The discs can maintain their shape after immersed in culture medium for 10 days, not including Mg Al LDH disc. The elastic modulus of all discs was between 9 and 35 GPa, which was close to cortical bone (5–23 GPa). Zn Al LDH and Zn Fe LDH showed higher cytotoxicity than Mg Al LDH and Mg Fe LDH whether in the form of suspension or extract. Furthermore, even up to 10 mg/mL, the extract of Mg Al LDH and Mg Fe LDH showed no cytotoxicity, while cells were totally died in the extract of Zn Al LDH and Zn Fe LDH. Compared with cells, bacterial showed an even lower tolerance concentration to Zn Al LDH and Zn Fe LDH. This study indicates that Mg-containing LDH show better cytotocompatibility, while Zn-containing LDH show better antibacterial property. With proper elastic modulus and controllable biological effect, LDH are promising to be used as bone implants. Highlights • Mg Al LDH, Mg Fe LDH, Zn Al LDH and Zn Fe LDH are prepared at pH 10. • Pressed Mg Al LDH disc is collapsed when immersed in solution. • The elastic modulus of all the pressed discs is in nature bone range. • Zn-containing LDH show higher toxicity to cells and bacteria than Mg-containing LDH. [ABSTRACT FROM AUTHOR]

Titanium and its alloys have been used extensively for orthopedic and dental implants. Although these devices have achieved high rates of success, two major complications may be encountered: the lack of osseointegration and the biomaterial-related infection. Accordingly, cerium oxide (CeO)-doped titanium oxide (TiO) materials were coated on titanium by an atmospheric plasma spraying (APS) technique. The phase structures, morphologies, and surface chemical states of the obtained coatings were characterized by x-ray diffraction, scanning electron microscopy, and x-ray photoelectron spectroscopy techniques. The in vitro antibacterial and cytocompatibility of the materials were studied with Staphylococcus aureus ( S. aureus, ATCC25923) and osteoblast precursor cell line MC3T3-E1. The results indicated that the addition of CeO shifts slightly the diffraction peaks of TiO matrix to low angles but does not change its rutile phase structure. In addition, the CeO/TiO composite coatings possess dose-dependent corrosion resistance and antimicrobial properties. And doping of 10 wt.% CeO exhibits the highest activity against S. aureus, improved corrosion resistance, and competitive cytocompatibility, which argues a promising option for balancing the osteogenetic and antibacterial properties of titanium implants. [ABSTRACT FROM AUTHOR]