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[Display omitted] • SDF-1α/CGRP-nHA/PDA/CMCS scaffold was constructed by 3D printing. • SDF-1α/CGRP-nHA/PDA/CMCS scaffold has 5-fold chemotaxis to rPDSC than factorless. • SDF-1α/CGRP-nHA/PDA/CMCS scaffold can promote the reactivation of bone inactivated. The repair of bone tumors is an urgent problem to be solved in clinical treatment. In this study, nano-hydroxyapatite (nHA), polydopamine (PDA) and carboxymethyl chitosan (CMCS) composite scaffolds loaded with stromal cell-derived factor-1α (SDF-1α) and calcitonin gene-related peptide (CGRP) were constructed by 3D printing. It was found that the chemotaxis of nHA/PDA/CMCS scaffold loaded with SDF-1α/CGRP factors to rat periosteal-derived stem cells (rPDSCs) was fivefold higher than that without factors loading, and the constructed scaffold had good biocompatibility and promoted the reactivation of bone inactivated by microwave thermal ablation. [ABSTRACT FROM AUTHOR]

The clinic application of magnesium is mainly impeded by its poor corrosion resistance and implants with localized drug delivery attract tremendous interest. Here, Mg/Al layered double hydroxide (Mg-Al LDH) film was in situ prepared on AZ31 alloy by a hydrothermal process, and further calcined to form metastable mixed oxides, also named Mg/Al layered double oxide (LDO). Finally, immersing in 5-Fluorouracil (5-FU) solution, Mg/Al LDO would revert to Mg/Al LDH via a memory effect, and be loaded with 5-FU (#LDO-5FU). Comparing to AZ31 alloy, the corrosion resistance of the as-prepared #LDO-5FU sample was enhanced. The amount of released 5-FU from #LDO-5FU sample was ∼993 ng/cm 2 . The proliferation of human cholangiocarcinoma cell (RBE) was effectively inhibited on the surface of #LDO-5FU sample owing to the release of 5-FU. This work broadens the application of calcined LDH and provides a new strategy in the field of surface modification of magnesium alloy. [ABSTRACT FROM AUTHOR]

• Hydroxyapatite/graphene oxide (HA/GO#) bilayer coating is prepared on AZ31 alloy via hydrothermal treatment and spin coating. • The presence of GO can effectively inhibit the formation and growth of cracks on HA layer. • HA/GO# coating shows enhanced corrosion resistance and biocompatibility. Fast degradation is the major limitation for biomedical application of Mg alloy. In the current work, a bilayer coating (HA/GO#) with hydroxyapatite as the inner layer and graphene oxide as the out layer was prepared on AZ31 alloy. Graphene oxide could sufficiently inhibit the formation and growth of corrosion cracks on hydroxyapatite layer, which result in its superior corrosion resistance. In vitro cell viability results suggested that MC3T3-E1 cells exhibited larger spreading area on HA/GO# coating at the initial 4 h of incubation. Furthermore, cells on HA/GO# coating showed superior proliferation rate. Considering its satisfied corrosion resistance and biocompatibility, the as prepared bilayer coating on AZ31 alloy is promising for clinical application. [ABSTRACT FROM AUTHOR]

• Mg-Li-Zn alloy with high Zn content (12 wt %) is subjected to solid solution treatment. • After solid solution treatment, α-Mg remains in β-Li matrix of Mg − Li − Zn alloy,. • After solid solution treatment, MgLiZn and MgLi 2 Zn phases disappear. • The treated Mg-Li-Zn alloy shows enhanced anti-corrosion and yielding strength. • The treated Mg-Li-Zn alloy shows improved osteogenesis induction capability. Microstructure, mechanical strength, corrosion resistance, and osteogenesis of as-cast Mg-11 wt% Li-12 wt% Zn alloy were investigated before and after solid solution treatment. Massive MgLiZn and MgLi 2 Zn phases were formed in the as-cast sample, resulting in micro-galvanic corrosion and high corrosion rate. After the solid solution treatment, the lath-shaped α-Mg phase remained in the β-Li matrix, whereas the large MgLiZn and MgLi 2 Zn phases dissolved in it, resulting in enhanced the corrosion resistance. Moreover, the yielding strength of the as-cast sample was improved from 136 to 260 MPa after treatment. In addition, the solid solution-treated Mg-Li-Zn exhibited improved induction of the alkaline phosphatase activity and osteogenesis-related gene expression in rBSMCs, confirming its promising potential for orthopedic applications. [ABSTRACT FROM AUTHOR]

• A self-healing coating was prepared on a magnesium surface using a simple deposition method. • The prepared coating exhibited excellent corrosion resistance and self-healing ability. • The prepared coating demonstrated good biocompatibility. To improve the corrosion resistance and biocompatibility of magnesium (Mg) for biomedical applications, a novel coating comprising self-healing dicalcium phosphate dihydrate (DCPD) was applied to Mg using a simple deposition method, without the need for the addition of corrosion inhibitors. Scratch and immersion tests demonstrated that the prepared coating displayed impressive self-healing capabilities, with artificial scratches within 4 h when exposed to 0.9 wt% NaCl solution. The electrochemical test suggested that the DCPD-coating, whether scratched or not, provided effective corrosion protection for the Mg substrate. In vitro cell culture results revealed that the DCPD-coated samples exhibited superior biocompatibility compared to pure Mg. This work offers a new perspective on designing self-healing coatings for Mg, eliminating the need for additional corrosion inhibitors. [ABSTRACT FROM AUTHOR]

Abstract: A novel method was employed to synthesize TiO2–SiO2/waterborne polyurethane (WPU) hybrid terminated by 3-aminopropyltriethoxylsilane (APTES) via a sol–gel process. The hybrids were synthesized by in situ hydrolysis and condensation of tetrabutyl titanate (TBOT) and APTES. TiO2–SiO2 particles were well dispersed in polymer matrix with a diameter of about 500nm and there was no phase separation between particles and WPU. XPS analysis demonstrated that TiOSi bonds existed in TiO2–SiO2/WPU hybrid, and the percentages of SiOTi bond in Si and Ti were about 35% and 20%, respectively. The chemical bonds between WPU and TiO2–SiO2 facilitated the homogenous dispersion and better compatibility during the sol–gel process. The successful preparation of TiO2–SiO2/WPU hybrid opens a new way to investigate other inorganic particles/WPU hybrids, such as Al2O3–SiO2/WPU for coating, fiber and adhesive applications. [Copyright &y& Elsevier]

Abstract: Porous hollow iron oxide nanoparticles (PHNPs) supported on carbon nanotubes (CNTs) were facilely synthesized by etching Fe@FexOy/CNT with dilute nitric acid aqueous solution at ambient temperature without the assistance of any surfactants and ligands. The mean diameter of hollow iron oxide nanoparticles was about 17nm, with a wall thickness of about 4nm. The formation mechanism of PHNPs is discussed based on the characterization results from TEM, XRD and H2-TPR. The combination of nanoscale Kirkendall effect and selective acid etching is proposed to be responsible for the formation of CNT supported PHNPs, through a transformation from core/void/shell structures to hollow nanoparticles. [Copyright &y& Elsevier]

[Display omitted] • The Zn-doped BST coating was successfully constructed on Ti surface. • Zn doping could improve the hydrophilicity of BST. • Zn doping showed significant inhibition of E. coli and S. aureus growth. Titanium (Ti) is a material commonly used in orthopedic implants. However, the lack of antimicrobial properties limits its application in implants. Herein, we constructed zinc (Zn)-doped barium strontium titanate (BST) films on Ti. The results show that the Zn-doped BST films can effectively improve the antibacterial ability of Ti substrates, which presents potential applications in bone repair. [ABSTRACT FROM AUTHOR]

• BiO 2 coatings are fabricated on Ti surface using magnetron sputtering. • BiO 2 coatings do not alter the surface morphology, wettability, and biocompatibility of Ti. • BiO 2 coated Ti shows enhanced osteogenesis and immune regulation abilities. Aseptic loosening often leads to orthopedic implantation failure. In this study, to improve the osteointegration of Ti orthopedic implants, bismuth oxide (Bi 2 O 3) layer was magnetron sputtering coated on Ti surface. The Bi 2 O 3 coating had few influence on the surface morphology and wettability of Ti. In vitro cell culture of rat bone marrow stem cells (rBMSCs) suggested that Bi 2 O 3 coating showed good cytocompatibility and was favorable for its osteogenic differentiation. Furthermore, the Bi 2 O 3 coating was found to induce macrophage cells (RAW264.7) polarize to anti-inflammatory phenotype, whereas inhibit its pro-inflammatory polarization. With improved osteogenesis and tissue repair immune regulation, the designed Bi 2 O 3 coating is promising for orthopedic applications. [ABSTRACT FROM AUTHOR]

In this work, the magnetic assembly combined with fast photopolymerization is applied for the preparation of mechano-responsive photonic hydrogel. The as-prepared hydrogel exhibits switchable color with ultrafast speed (Δλ/t=~1.2 nm/ms) across a broad wavelength range (Δλ=~250 nm), which is attributed to fast changing of the interparticle distance d of one dimensional (1 D) Fe 3 O 4 nanoparticle chains fixed inside the hydrogel matrix in response to compressive force stimulus. The pressure chromatic sensitivity is high (Δλ/σ=20–40 nm kPa −1 ) in touch region. With the aid of 3D printing technique, we innovatively demonstrate simultaneous multicolor displays on the hydrogel. [ABSTRACT FROM AUTHOR]

Non-noble metals are attractive alternatives to Pt co-catalysts for hydrogen production. Herein, Co nanoparticles were designed to uniformly deposit on the surface of TiO 2 nanotube arrays (Co/TNAs) via photo-deposition and reduction method. The structure and optical property of the Co/TNAs were characterized. Compared with pure TNAs, Co/TNAs showed a highly photocatalytic activity for hydrogen production without the Pt co-catalyst under UV–vis light irradiation. The study presents a promising practical way using non-noble metal as co-catalyst for photocatalytic splitting of water into hydrogen. [ABSTRACT FROM AUTHOR]

To decrease the high cost of cathodic electrocatalysts caused by platinum-based catalysts in fuel cells, a series of silicon-doped carbon nanotubes with different Si contents were synthesized by the thermolysis of trimethylphenylsilane and xylene and used as low-cost metal-free catalysts for the oxygen reduction reaction (ORR). Electrochemical tests showed that the electrocatalytic activities of the synthesized Si-doped carbon nanotubes towards the ORR all were higher than that of pure carbon nanotubes and their ORR activities did not enhance proportionally with the increase of silicon doping content in alkaline medium, indicating a promising potential for designing low-cost and efficient metal-free electrocatalysts in future alkaline fuel cell devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zn-Al layered double hydroxides (LDHs) films were constructed on Zn substrate via simple hydrothermal treatment. • The LDHs films can effectively improve the corrosion resistance of Zn. • The LDHs films present enhanced cytocompatibility and do little harm to cells. Zinc (Zn) is promising candidate to construct biodegradable medical devices. However, the poor corrosion resistance limits its clinical application. Herein, Zn-Al layered double hydroxide (LDH) films were constructed. Results showed that Zn-Al LDHs films could effectively enhance the anti-corrosion ability and biocompatibility of the Zn substrate, which provided new insights in the surface modification of Zn. [ABSTRACT FROM AUTHOR]

To design low-cost and efficient cathode electrocatalysts and push forward the commercialization of fuel cells, low platinum content catalyst supported on nitrogen and phosphorus-codoped carbon nanotubes (Pt/NP-CNTs) for the oxygen reduction reaction (ORR) were prepared. Electrochemical tests demonstrated that the Pt/NP-CNTs catalyst exhibited much high ORR activity and remarkable stability in acidic media due to the strong interaction between NP-CNT support and Pt catalyst evidenced by the calculation of the density functional theory, showing a good potential application for a future low-cost proton exchange membrane fuel cell device. [ABSTRACT FROM AUTHOR]

• Ti coatings are prepared on pure Zn via magnetron sputtering technology. • The presence of Ti coatings can effectively inhibit the release of Zn ions from the substrate. • The Ti-coated Zn show enhanced corrosion resistance and biocompatibility. Recently, Zn and its alloys are hotspots in biodegradable implants for their desirable degradation rate. In this study, Ti coatings are deposited on Zn by magnetron sputtering to enhance its corrosion resistance and biocompatibility. The surface morphology and chemical compositions of the coatings are studied by SEM, XRD, and XPS. Though obvious Ti elements are detected on the surface of the coatings, the surface views do not change after deposited with Ti. Potentiodynamic polarization, Zn ion release, and corrosion morphology observations suggest that Ti coatings can improve the corrosion resistance of Zn. The cells cultured in the extracts of Ti-coated samples exhibit higher viability than those cultured in the extract of Zn. With enhanced corrosion resistance and cytocompatibility, Ti-coated Zn is believed to be a candidate coating for implant application. [ABSTRACT FROM AUTHOR]