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Electrospun composite nanofibrous scaffolds have been regarded as a potential carrier for local drug delivery to prevent tumor recurrence. Herein, a model drug (paclitaxel) was creatively loaded into lignin nanoparticles (PLNPs) and then encapsulated into the polymer of poly (vinyl alcohol)/polyvinyl pyrrolidone which has been fabricated into a composite nanofibrous membrane (PVA/PVP-PLNPs) for use as a drug carrier using the electrospinning technique. The fabricated PVA/PVP-PLNPs membranes exhibited good particle distribution, mechanical properties, thermal stability and biocompatibility. In vitro experiments showed that combining lignin nanoparticles by electrospinning not only improved the drug release profile, but also enhanced the hydrophilicity of nanofibrous membranes which was beneficial to cell adhesion and proliferation. Cellular experiments demonstrated that PVA/PVP-2%PLNPs membrane showed good cell inhibition ability, and the cell survival rate was only 21% at day 7. It indicates that the as-prepared PVA/PVP-PLNPs composite nanofibers are promising candidates for local anticancer therapy. [ABSTRACT FROM AUTHOR]

In this study, porous TiO 2 /HA coating and petaling structured TiO 2 /HA coatings were prepared by micro-arc oxidation (MAO) on titanium (Ti) surface to enhance biocompatibility. Morphology, phase composition, roughness and hydrophilicity were separately investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), atomic force microscope (AFM), and contact angle meter. The biocompatibility was evaluated by in vitro cell co-culture experiment. The results revealed that, the surface roughness and hydrophilicity of petaling structured TiO 2 /HA coatings were much larger than that of the porous structured TiO 2 /HA. And with the increased density of the HA petals, the roughness and hydrophilicity increased. MC3T3-E1 cell adhesion, spreading, proliferation and ALP expression were most enhanced on TiO 2 /HA coatings with the maximum density of HA petals. The beneficial effect of structures on biocompatibility may be due to the improved surface roughness and hydrophilicity. [ABSTRACT FROM AUTHOR]

In this paper, the titanium (Ti) surfaces with different structure, composition, crystal form and grain size are prepared by micro arc oxidation and thermal treatment, and then their hydrophilicity and surface roughness are investigated. The experimental results show that there is no necessary relationship between hydrophilicity and surface roughness. For hydroxyapatite (HA) coatings with different surface structures, the structure with more HA amount has better hydrophilicity. And, with the same porous structure, HA surface endows better hydrophilicity than TiO 2 . Anatase surface with small grain size has better hydrophilicity and rutile has better hydrophilicity than anatase. Combined with their biological properties which have been well reported, the dependent relationship of hydrophilicity and biological properties can be concluded, namely the good biological properties can be obtained by improving the hydrophilicity. This research work sheds light on the methods for optimization of biological properties of the implant materials. [ABSTRACT FROM AUTHOR]

The hierarchical micro-nanostructure has been proved to endow titanium (Ti) surface with good biological properties. However, to achieve satisfied osseointegration, good corrosion resistance and mechanical properties are also necessary. Therefore, in this paper, the corrosion resistance and mechanical properties of the Ti implant with hierarchical micro-nanostructure were investigated. The corrosion resistance was detected by polarization curve test, and the mechanical properties were evaluated by friction-wear experiment and nano indentation test. The results showed that the micro-nanostructured Ti surface showed increased corrosion potential, and it also showed decreased friction coefficient, stiffness and Young´s modulus, similar to that of the cortical bone. The improved corrosion resistance and mechanical properties might endow the micro-nanostructured Ti implant with good osseointegration and promising application in clinic. [ABSTRACT FROM AUTHOR]

A hydroxyapatite (HA)/TiO 2 composite coating was prepared on a titanium surface by one-step micro-arc oxidation (MAO). The formation mechanism of the composite coating was investigated and the adhesion of the coating to the substrate was also measured. The results showed that flocculent structures could be obtained during the early stages of treatment. As the treatment period extended, increasing amounts of Ca–P precipitate appeared on the surface, and the flocculent morphology transformed into a plate-like morphology. Then the plate-like calcium and phosphate salt self-assembled to form flower-like apatite. The Ca/P atomic ratio gradually decreased, indicating that the amounts of Ca 2+ ions which diffused into the coating decreased more rapidly than that of PO 4 3− or HPO 4 2− . The adhesive strength between the apatite and TiO 2 coating was improved. This improvement is attributed to the interlocking effect between the apatite and TiO 2 layer which formed simultaneously during the early stages of the one-step MAO. This study shows that it is a promising method to prepare bioactive coating on a titanium surface. [ABSTRACT FROM AUTHOR]

TiO 2 nanotube arrays were synthesized on Ti surface by anodic oxidation. The elements of Ca and P were simultaneously incorporated during nanotubes growth in SBF electrolyte, and then Ag was introduced to nanotube arrays by cathodic deposition, which endowed the good osseointegration and antibacterial property of Ti. The bioactivity of the Ti surface was evaluated by simulated body fluid soaking test. The biocompatibility was investigated by in vitro cell culture test. And the antibacterial effect against Staphylococcus aureus was examined by the bacterial counting method. The results showed that the incorporation of Ca, P and Ag elements had no significant influence on the formation of nanotube arrays on Ti surface during electrochemical treatment. Compared to the polished or nanotubular Ti surface, TiO 2 nanotube arrays incorporated with Ca, P and Ag increased the formation of bone-like apatite in simulated body fluid, enhanced cell adhesion and proliferation, and inhibited the bacterial growth. Based on these results, it can be concluded that the nanostructured Ti incorporated with Ca, P and Ag by electrochemical method has promising applications as implant material. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ti surface was modified by anodic oxidation and ultraviolet irradiation. [•] Surface modification improved the biological properties of Ti. [•] The mechanisms of surface modification on biological properties of Ti was studied. [ABSTRACT FROM AUTHOR]

Abstract: In this work, plasma sprayed nano-titania/silver coatings were deposited on titanium substrates to obtain an implant material having excellent antibacterial property. The surface characteristics of nano-titania/silver coatings were investigated by scanning electron microscopy, energy dispersive spectrometer, optical emission spectrometry and X-ray diffraction. The bioactivity of nano-titania/silver coatings was examined by simulated body fluid soaking test. The antibacterial activity against Escherichia coli was examined by bacterial counting method. The cytocompatibility and in vitro osteotoxicity was evaluated by alamarBlue™ Assay using MG-63 osteoblasts. The results showed that nano-titania/silver coatings still had good bioactivity. Silver existed homogeneously in the nano-titania coating as silver oxide and metal silver, which ensured a sustained release of silver for 28 days. The loaded silver had no obvious osteotoxicity, while showed strong inhibition against the growth of Escherichia coli. [Copyright &y& Elsevier]

Although Ti is widely used in orthopedic implants, its bio-inert characteristics and poor antibacterial activity may result in implant failure. To counter this problem, in this study, we loaded simvastatin, a bioactive compound that promotes osteogenesis, in TiO 2 nanotubes and a thermosensitive chitosan-glycerin-hydroxypropyl methyl cellulose hydrogel (CGHH) was then layered on top of these nanotubes. At normal human-body temperature (37 °C), CGHH was present in a sol state, thus facilitating the controlled release of simvastatin to enhance differentiation in MC3T3-E1 osteoblasts. In vitro cell-culture studies suggested that CGHH in a gel state would induce macrophage polarization to the pro-inflammatory M1 phenotype. In vitro testing against Escherichia coli and Staphylococcus aureus indicated no antibacterial activity in CGHH in both sol and gel states. However, the results of subcutaneous infection animal models suggested that CGHH showed excellent in vivo antibacterial activity, which can be explained by the fact at high temperatures induced by an infection, CGHH transitioned into a gel state and released large amounts of glycerin. Such a high glycerin dosage induced an acute inflammatory reaction and antibacterial activity. Thus, due to their enhanced osteogenesis capacity at normal body temperature and antibacterial characteristics in the presence of infection, the newly designed simvastatin-loaded CGHH-encapsulated TiO 2 nanotubes are promising materials for application in orthopedic implants. Unlabelled Image • Thermo-sensitive hydrogel (CGHH) is formed by mixing hydroxy propyl methyl cellulose, chitosan and glycerine. • Thermo-responsive drug loading system (Sim@CGHH) is constructed by coating CGHH on a simvastatin (Sim) loaded nanotubular titanium. • Sim@CGHH is biocompatible and can promote osteogenesis differentiation. • Sim@CGHH can regulate immunoreaction in a thermo-responsive manner. [ABSTRACT FROM AUTHOR]

A proper immune response is a key to successful implantation of biomaterials. Since the dynamic changes of the human body's microenvironment, the required immune response should alter along with the microenvironment. A thermo-sensitive hydrogel composed of biocompatible hydroxypropyl methylcellulose (HMPC), chitosan (CS), and glycerin (Gly) was introduced on the anodized titanium surface to regulate the immune response. The results showed that the encapsulated hydrogel can cause macrophages to polarize toward the M2 phenotype, and promote tissue repair in the sol state at normal body temperature, while at the high-temperature induced by a bacterial infection, it will turn to a gel state, and can cause macrophages to polarize toward the M1 phenotype, promote inflammation, to realize an intelligent identification and regulation of the physiological environment, thus to satisfy the changeable immunity demands. By changing the temperature of the thermosensitive hydrogel, the transformation between macrophages M1 and M2 could be achieved, and the tissue could be transferred between the inflammatory stage and the healing stage promptly to achieve the purpose of antibiosis or tissue repair. The immunomodulatory effect of the thermo-sensitive hydrogel was verified to be related to the varied HMPC, CS, and Gly release in the sol and gel states. Unlabelled Image • Hydrogel composed of hydroxy propyl methyl cellulose, chitosan and glycerine was coated on the anodized titanium surface. • The HPMC, CS and Gly release can be controlled by the temperature of the microenvironment. • The samples can induce macrophages polarizing toward M1 or M2 phenotype depending on the local temperature. • The system can induce an intelligent shift between tissue-healing and pro-inflammatory microenvironment based on immune needs. [ABSTRACT FROM AUTHOR]

Deep levels in heavily aluminum-doped zinc oxide (AZO) thin film were studied by transient capacitance (C-t) measurements and photoemission spectroscopy (PES). To study degenerated AZO by C-t measurements, AZO films were deposited on a p-type silicon (p-Si) substrate to form a depletion layer at the AZO/p-Si interface. Analyses of C-t behavior revealed that concentration of a trap level 0.3 eV below the bottom of the conduction was on the order of 1019 cm-3, which is 20%-50% of the shallow donor concentration. Such a high concentration of the trap level in AZO was evidenced by subsequent PES measurements. [ABSTRACT FROM AUTHOR]

Abstract: In this work, the plasma sprayed wollastonite coating was soaked in 5wt% AgNO3 solution at room temperature to load silver for improving its antibacterial effect. The surface characteristics of the silver-loaded coating were investigated by SEM, EDS and XRD. The release rate of silver from the coating was measured by ICP-OES in deionized water. The osteotoxicity of the silver-loaded coating was evaluated by in vitro cell culturing test. The antibacterial activity against Staphylococcus aureus was examined by Zone of Inhibition test. The results showed that the loaded silver reacted with the wollastonite coating to form silver silicate, which ensured a sustained release of silver in deionized water for as long as 50 days. The antibacterial activity and cell culturing tests confirmed that the silver released from silver-loaded wollastonite coating had strong inhibition against the growth of S. aureus, while they did not exhibit any adverse effects on the osteoblasts proliferation. [Copyright &y& Elsevier]

• A novel sulfur host was preparation by facile spray drying method. • The three-dimensional interwoven CNT facilitate the transfer of Li+ and electron. • Polar Fe 3 O 4 nanoparticles can effectively prevent the dissolution of polysulfide. • The S/CNT/Fe 3 O 4 cathode has excellent capacity decay rate per cycle. Lithium-sulfur batteries were considered as a new generation of high energy density batteries, but their commercialization was limited by volume expansion, the low conductivity of sulfur and shuttle effect. To overcome these issues, we developed a three-dimensional carbon nanotube/Fe 3 O 4 microspheres via spray drying and calcination as sulfur host materials (S/CNT/Fe 3 O 4). In this three-dimensional microsphere structure, interwoven CNT backbone offers a robust conductive network with sufficient space for loading sulfur, and the polar Fe 3 O 4 nanoparticles can enhance chemical adsorption of polysulfide. Benefiting from these advantages, the S/CNT/Fe 3 O 4 cathode exhibit high initial discharge capacity (1270 mAh g−1 at 0.2 C), superior rate performance (602 mAh g−1 at 3 C), and long cyclic stability (only 0.084% capacity decay per cycle for 300 cycles at 1 C). [ABSTRACT FROM AUTHOR]

Titanium (Ti) is the widely used implant material in clinic, however, failures still frequently occur due to its bioinertness and poor antibacterial property. To improve the biological and antibacterial properties of Ti implants, micro-nanostructured hydroxyapatite (HA) coating was prepared on Ti surface by micro-arc oxidation (MAO), and then the antibacterial agent of chitosan (CS) was loaded on the HA surface through dip-coating method. The results showed that the obtained HA/CS composite coating accelerated the formation of apatite layer in SBF solution, enhanced cell adhesion, spreading and proliferation, and it also inhibited the bacterial growth, showing improved biological and antibacterial properties. Although, with the increased CS amount, the coverage of HA coating would be enlarged, resulting in depressed biological property, however, the antibacterial property of the composite coating was enhanced, and the cytotoxicity about CS was not detected in this work. In conclusion, the HA/CS coating has promising application in orthopedics, dentistry and other biomedical devices. [ABSTRACT FROM AUTHOR]

The commercialization of Lithium-sulfur batteries was limited by the polysulfide shuttle effect, and modifying the routine separator was an effective method to solve this problem. In this work, a novel hierarchically porous polypyrrole sphere (PPS) was successfully prepared by using silica as hard-templates. As-prepared PPS was slurry-coated on the separator, which could reduce the polarization phenomenon of the sulfur cathode, and efficiently immobilize polysulfides. As expected, high sulfur utilization was achieved by suppressing the shuttle effect. When tested in the lithium-sulfur battery, it exhibited a high capacity of 855 mAh·g−1 after 100 cycles at 0.2 C, and delivered a reversible capacity of 507 mAh·g−1 at 3 C, showing excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Lithium/sulfur (Li/S) batteries have received great attention due to their high theoretical energy density, but the "shuttle effect" of polysulfides restricts the further development of Li/S batteries. The construction of modified functional separator is an effective strategy to obstruct the diffusion of polysulfides. We report boron-doped graphene and activated carbon (B-G/AC)-modified functional separator for Li/S batteries. The B-G/AC composites are obtained via a one-step hydrothermal method and used as a functional layer to modify the battery separator. The B-G with highly porous three-dimensional (3D) network structure exhibits good electrical conductivity, and rich porous structure AC increases the specific surface area of the B-G/AC composite. The carbon coating layer can act as the second collector, utilizing the inactivated sulfur that is freed in the electrolyte. The modified separator can facilitate the polysulfide dissolution and migration towards the anode. The B-G/AC samples exhibit excellent electrochemical performances. The B-G/AC samples maintain a higher capacity of 1062 mA h g−1 after 100 cycles at 0.1 C than a routine separator (709 mA h g−1 after 100 cycles at 0.1 C). Diffusion experiments of polysulfides in U-shaped bottles also proved importance of B-G/AC as a separator. In addition, the B-G/AC samples also exhibit excellent cycling stability over 300 cycles, delivering a discharge capacity of 534 mA h g−1 when the current is 1 C. The present study confirms that separator modification is an effective technique that leads to good electrochemical performance.Long-term cyclic performance of Li/S batteries with different separators at 1 C and photograph of polysulfide diffusion process across with B-G/AC separator. [ABSTRACT FROM AUTHOR]

• Novel implant materials (Mg-Bi, MAO treated Mg and Mg-Bi) were proposed and prepared. • Element Bi and MAO treatment can improve the corrosion resistance of Mg dramatically. • Mg-Bi alloy has a greater potential to be used as an implant material. Mg-Bi alloy was prepared by metallurgical method and then surface treated by micro-arc oxidation (MAO) in this work. The influence of element Bi and MAO treatment on the corrosion resistance of Mg matrix was investigated. The results showed that, element Bi can obviously improve the corrosion resistance of Mg (2–3 orders of magnitude), which may be due to that the formation of Mg 3 Bi 2 particles can refine the grain size of the Mg matrix. After MAO treatment, the corrosion resistance was further enhanced and the MAO treated Mg-Bi showed the best corrosion resistance, however the improvement of MAO coatings is not very huge (about two times of Mg-Bi alloy). Considering the nonuniform structure, easy degradation and instability of coating materials, Mg-Bi alloy without MAO treatment has a greater potential to be used as an implant material in clinics. [ABSTRACT FROM AUTHOR]

Abstract Antibacterial porcelain layers were synthesized on Ti by laser-fusion method. The specimens were studied by XRD, FE-SEM, EDS, scratching test and anti-bacterial tests. The main crystalline phases of the antibacterial coatings are TiO 2 and CaTiO 3 , which are mainly caused by the metallurgical chemical reaction between the coating and the Ti-substrate during the process of the laser fusion. Due to the high temperature gradient perpendicular to the laser scanning direction, a coating with dendrites structure was formed on Ti. More dendrites are formed when the Ti content was increased, resulting in the greater roughness of the coating surface. The scratching bonding strength between the coating and Ti substrate reaches the maximum value (93.63 MPa) at Ti content of 20 wt%, which are much higher than the regular bonding strength between the common fused porcelain and Ti (only about 35–40 MPa). After cultivation for 10 h, the nano-silver particles embedded in antibacterial coating began to take on the role of the sterilization, and the higher the silver content was, the better the anti-bacterial properties of the coatings were. However, the Ti content did not significantly affect the anti-bacterial properties of the coatings at the same Ag content of 2 wt%. A granular hydroxyapatite layer was deposited on the antibacterial coating's surface after immersion in simulated body fluid, which demonstrated good bioactivity of the coatings. Highlights • Laser fusion was used to form an antibacterial porcelain layers on Ti. • The bonding strength of the coating is much higher than that of common fused. • The Ti content did not affect the coating's anti-bacterial properties. • A granular HA layer was deposited on the antibacterial coating's surface. [ABSTRACT FROM AUTHOR]

Carbon nanotube (CNT)-reinforced mesoporous hydroxyapatite (HA) composites with excellent mechanical and biological properties were fabricated successfully by the in situ chemical deposition of mesoporous HA on homogeneously dispersed CNTs. The CNTs are first synthesized in situ on HA nanopowders by chemical vapor deposition, and then, the HA particles with mesoporous structures are deposited in situ onto the as-grown CNTs by using cetyl trimethyl ammonium bromide as templates to form mesoporous HA encapsulated CNTs (CNT@meso-HA). The modification of CNTs by mesoporous HA leads to strong CNT-HA interfacial bonding, resulting in efficient load transfer between CNT and HA and improved mechanical properties of CNT/HA composites. More importantly, the mesoporous HA structure has a high specific surface area and large surface roughness that greatly promote the cell adhesion and proliferation, resulting in better biocompatibility and improved osteoblast viability (MC3T3-E1) compared to those fabricated by traditional methods. Therefore, the obtained CNT@meso-HA composites are expected to be promising materials for bone regeneration and implantation applications. [ABSTRACT FROM AUTHOR]

Carbon nanotube (CNT)-reinforced hydroxyapatite (HA) composites were successfully fabricated by a double in situ synthesis process, which combined the in situ synthesis of CNTs in HA powders by chemical vapor deposition (CVD) with the further encapsulation of CNTs using HA by a sol–gel method. This double in situ synthesis approach not only improves the homogeneous dispersion of CNTs within the HA matrix, but also enhances the interfacial bonding between the CNTs and HA, thus leading to enhanced mechanical properties. Flexural tests indicated that the flexural strength of the composite is 1.6 times higher than that of pure HA, and significantly higher than that of the commercial and in situ synthesized CNT/HA composites. Furthermore, the in vitro cell culture experiments indicated that the CNT/HA composites fabricated by this double in situ process significantly accelerate the proliferation of fibroblast cells (L-929), compared with those fabricated by traditional methods, confirming their biocompatibility. With this biocompatibility and excellent mechanical properties, the obtained CNT/HA composites have a high potential as biomaterials, particularly in bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

[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]

Highlights: [•] Polycrystalline bulk compound LaZnAsO was synthesized for the first time. [•] Oxygen deficiency was introduced up to 35at.% under a high pressure of 6GPa. [•] The semiconductivity was highly robust against the oxygen deficiency up to 25at.%. [ABSTRACT FROM AUTHOR]

The durability of dental implants is closely related to osseointegration and surrounding soft tissue sealing. Appropriate local pH favors fibroblasts adhesion and contributes to soft tissue sealing. Layered double hydroxides (LDHs) are characterized by adjustable alkalinity, offering a possibility to investigate the influence of pH on cellular behaviors. Herein, we fabricated Mg Fe LDHs modified titanium. During calcination, the local pH value of LDHs increase, without altering other physics and chemical properties via OH− exchange mechanism. In vitro studies showed that LDHs films calcined at 250 °C for 2 h provide a local pH of 10.17, which promote early adhesion, proliferation, and type I collagen expression of human gingival fibroblasts (hGFs) through the formation of focal adhesion complex and activation of focal adhesion kinase related signaling pathways. In conclusion, endowing the titanium surface with appropriate alkalinity by Mg Fe LDHs films enhances the adhesion of hGFs, providing a new strategy of designing multifunctional biomaterials for soft tissue sealing around dental implants. [Display omitted] • Mg-Fe layered double hydroxides (LDHs) are prepared on titanium surfaces through a one-step hydrothermal treatment. • After calcination, three LDHs films show different local pH via OH- exchange, while other properties remain the same. • LDHs films enhance early adhesion ability of gingival fibroblasts in vitro. • The enhanced adhesion is due to up-regulation of FA complex related genes, especially FAK-related signaling pathways. [ABSTRACT FROM AUTHOR]

• Nanoporous bimetal Cu-Ag (NP-CuAg) is firstly used as the anodizing substrate. • Cu x O nanowires modified by Ag nanoparticles uniformly grow on NP-CuAg substrate. • The Ag/Cu x O@NP-CuAg composite exhibits excellent antibacterial activity. • The work offers an idea to form multicomponent material with various structures. Nano-sized bimetal, bimetallic oxides and their composites have aroused widespread research interests because of their multifunctional performances. The development of their novel structures and synthesis techniques is urgently needed. Herein, we fabricated a novel Ag nanoparticles modified Cu x O (x = 1, 2) nanowires on nanoporous copper-silver network (Ag/Cu x O@NP-CuAg) with hierarchical porous structure through dealloying and anodizing process. Nanoporous CuAg bimetal network (NP-CuAg), prepared by dealloying of Cu 40 Zr 50 Ag 10 metallic glass (MG) ribbon, was used as the anodizing substrate to provide bimetal sources for the first time. Then Ag nanoparticles modified Cu x O (x = 1, 2) nanowires were synthesized on NP-CuAg network by anodizing and calcination. Due to the unique structure and the synergistic effect of Cu and Ag elements, the as-obtained composite presents good antibacterial activity and a wide application prospect as a multifunctional material. [ABSTRACT FROM AUTHOR]

The application of lithium/sulfur (Li/S) batteries is negatively affected by the insulation of sulfur and large volumetric change during the cycles as well as the polysulfides dissolution. To solve the above problems, we fabricated a composite interlayer for Li/S batteries using ZnO nanocrystals anchored on connected carbon nanotube and graphene. The preparation of ZnO/carbon nanotube/reduced graphene oxide (ZnO/CNT/RGO) composite film was inspired from the combination of a one-step sol-gel synthetic technique and vacuum-assisted filtration. The ZnO/CNT/RGO interlayer showed effective adsorption of polysulfides during diffusion experiments. This ZnO/CNT/RGO interlayer can efficiently increase sulfur utilization by immobilizing soluble intermediate polysulfides. When used as a composite interlayer in Li/S batteries, an impressive high capacity of 768 mAh g−1 at 0.2C was achieved after 150 cycles and improved rate performance of 597 mAh g−1 at 2C was obtained. This study offers a facile method to improve the electrochemical performance of the Li/S batteries. Image 1053 • A novel ZnO/CNT/RGO composite interlayer were synthesized by sol-gel technique. • The ZnO/CNT/RGO film exhibits good cycling and rate capability for the Li–S batteries. • The ZnO/CNT/RGO interlayer can efficiently increase the utilization of sulfur. [ABSTRACT FROM AUTHOR]

Carbon-encapsulated Fe-C (Fe-C@C) nanoparticles with a divergently flower-like morphology were successfully synthesized for application as an adsorbing material by using freeze-drying and chemical vapor deposition (CVD) methods. The Fe metallic source was first loaded onto a sodium chloride (NaCl) supporter via freeze-drying to obtain the Fe/NaCl composite powder. Then, Fe-C@C nanoparticles were synthesized in the temperature range of 300–450 °C via CVD of acetylene in the Fe/NaCl composite powder using Fe nanoparticles as catalysts and NaCl as supporters. Because the NaCl supporter is water-soluble, the synthesized Fe-C@C nanoparticles were easy to purify, and a high purity was obtained by simple washing and centrifugation. The optimal Fe-C@C nanoparticles, synthesized at 400 °C, possessed a unique divergently flower-like structure and a high specific surface area of 169.4 m2/g that can provide more adsorption sites for contaminants. Adsorption experiments showed that the flower-like Fe-C@C adsorbent exhibited high adsorption capacity (90.14 mg/g) and fast removal of methylene blue (MB). Moreover, the magnetic properties of the nanoparticles, with saturation magnetization of 36.544 emu/g, facilitated their magnetic separation from wastewater. Therefore, the novel flower-like Fe-C@C nanoparticles with integrated adsorptive and magnetic properties have the potential to be an effective adsorbent in dye wastewater treatment. [ABSTRACT FROM AUTHOR]

Abstract A novel carbon nanotubes (CNTs)-reinforced magnesium (Mg) matrix composite was successfully fabricated via an in situ synthesis of Mg on the surfaces of CNTs and a powder metallurgy (PM) process. The nanoscale Mg grains were first synthesized in situ on CNTs via the solid-state displacement reaction of lithium (Li) to Mg in anhydrous magnesium chloride (MgCl 2) to obtain Mg-encapsulated CNTs (CNTs@Mg) composite powders. These were used to fabricate CNTs@Mg bulk composites via the PM method. In the CNTs@Mg in situ composite structure, the synthesized Mg grains were in contact with CNTs in a stacking manner, and nanoscale contact and diffusion bonding occurred at the CNTs–Mg interface, realizing not only strong interface bonding between CNTs and Mg but also the dispersion of CNTs in the Mg matrix. The CNTs@Mg composites exhibited improved mechanical properties. The microhardness, ultimate tensile strength (UTS), and breaking elongation of 4.0 wt% CNTs@Mg bulk composite were increased by approximately 43.5%, 33.4%, and 31.3% compared with pure Mg bulk, respectively. Furthermore, the mechanical properties of the CNTs@Mg bulk composites were superior to those of CNT/Mg composites fabricated via the traditional addition process. Therefore, the investigated CNTs@Mg composites are promising candidates for the field of lightweight structural materials. Graphical abstract Image 1 Highlights • A novel CNTs@Mg composite was fabricated via solid-state displacement and PM methods. • Mg grains formed by heterogeneous nucleation coat the CNT surfaces to form CNTs@Mg. • CNTs as nucleation sites of Mg grains remarkably refine the grain size of Mg matrix. • Nanoscale contact and diffusion bonding of CNTs-Mg realize their tight combination. • CNTs@Mg composites exhibit improved mechanical properties. [ABSTRACT FROM AUTHOR]

Abstract A novel magnetic targeted drug delivery carrier based on a carbon nanotube (Fe)/hydroxyapatite (CNT(Fe)/HA) composite was successfully fabricated by an in situ synthesis of CNTs in HA nanopowder using Fe catalysts and subsequent chemical modification of the as-fabricated CNT(Fe)/HA by chitosan (CS) and folic acid (FA) for a controllable release of an anticancer drug doxorubicin (DOX). The synthesized CNTs, Fe, and HA self-assembled into a composite structure in situ during the synthesis. After the acid treatment, the CNTs were shorter and homogeneously dispersed, the tips of the CNTs were opened, and oxygen-containing functional groups were introduced onto the CNTs. Upon the functional modification through the surface coating with CS and FA, the functionalized CNT(Fe)/HA became capable of loading DOX through both π–π stacking and electrostatic adsorption of FA. The results showed that the average drug-loading rate of DOX was 130 wt%. Furthermore, the pH response of FA-CS-CNT(Fe)/HA enabled the release of a large amount of DOX in phosphate-buffered saline (PBS) at pH = 5.5 with an average drug release rate of 52 wt% after 72 h. In contrast, the drug release in PBS at pH = 7.4 was only 8 wt%. In addition, the saturation magnetization, coercive force, and remanence to saturation magnetization ratio of DOX-FA-CS-CNT(Fe)/HA were 0.88 emu g−1, 668.96 Oe, and 0.44, respectively, indicating its potential for drug transport under strong external magnetic fields, which could enable magnetic targeted delivery. Graphical abstract Unlabelled Image Highlights • A carbon nanotube (CNT) (Fe)/hydroxyapatite (HA) in situ composite was fabricated. • CNT(Fe)/HA composite was chemically modified by chitosan (CS) and folic acid (FA). • FA-CS-CNT(Fe)/HA can load doxorubicin (DOX) to form a drug delivery system. • FA-CS-CNT(Fe)/HA exhibits a high drug-loading rate and pH response. • FA-CS-CNT(Fe)/HA possesses ferromagnetism to realize a magnetic targeted effect. [ABSTRACT FROM AUTHOR]

Abstract The titanium surface was laser-nitrided to form a TiN intermediate layer and then a bonding porcelain layer was laser fused on it. The specimens were studied by XRD, FE-SEM and EDS tests. A porous titanium nitride layer about 20 μm was synthesized on Ti surface, and the main phases of which were c-TiN and TiN 0.3. The Vickers hardness of the TiN layer was 618.68 HV, which is about 3 times of the titanium (202.9 HV). The EDS results showed the TiN layer prepared at 300W was a non-stoichiometri compound with mole ratio of Ti to N about 1:0.621. The porcelain coating laser fused on the TiN layer inherited the columnar structure of TiN, which had a rhombus-like intersecting surface. The highest scratching bonding strength (193.21 ± 23.33 MPa) between TiN layer and Ti was obtained at nitriding power of 300W. The porcelain coating laser fused on the TiN layer inherited the columnar structure of TiN, which had a rhombus-like intersecting surface. The bonding strength between coating and titanium (67.28 MPa) were much higher than the regular bonding strength between the porcelain and Ti (only about 35–40 MPa), which could be ascribed to the good chemical reactivity and wettability between the TiN layer and porcelain. Highlights • A non-stoichiometri TiN layer was prepared on Ti by laser nitriding. • The laser nitriding improved the wettability between the porcelain and Ti. • Good chemical reactivity and wettability enable the good bonding strength. [ABSTRACT FROM AUTHOR]

A novel carbon nanotube (CNT)-alumina (Al 2 O 3 ) synergistically reinforced magnesium matrix composite was successfully fabricated by the in situ synthesis of vertically dispersive CNTs self-organized on Al 2 O 3 microspheres using catalytic chemical vapor deposition (CCVD) and powder metallurgy (PM) methods. Using the CCVD method, the in situ synthesized CNT-Al 2 O 3 synergistic reinforcements presented an urchin-like and spherically symmetrical structure, and were prone to staggered arrangement with each other. Using the PM process, the CNT-Al 2 O 3 reinforcements were homogeneously distributed and formed close-knit interfacial bonds with the Mg matrix. Combining the strengthening effects of CNTs and Al 2 O 3 microspheres, the mechanical properties of the CNT-Al 2 O 3 /Mg composite were improved apparently. The ultimate tensile strength and elongation to failure of the CNT-Al 2 O 3 /Mg composite increased by approximately 26.8% and 20.9% compared to those of pure Mg bulk, respectively, and its hardness was 38.9% higher than that of pure Mg. Furthermore, the mechanical properties of the CNT-Al 2 O 3 /Mg composite were significantly higher than those of Al 2 O 3 /Mg and CNT/Mg composites, indicating its excellent synergistically reinforcing effects. Therefore, the obtained CNT-Al 2 O 3 /Mg composite is expected to be a promising material for application in the field of lightweight structural materials. [ABSTRACT FROM AUTHOR]

Bonding porcelain layer was fused on Ti surface by laser cladding process using a 400 W pulse CO 2 laser. The specimens were studied by field-emission scanning electron microscopy, X-ray diffraction and bonding tests. During the laser fusion process, the porcelain powders were heated by laser energy and melted on Ti to form a chemical bond with the substrate. When the laser scanning speed decreased, the sintering temperature and the extent of the oxidation of Ti surface increased accordingly. When the laser scanning speed is 12.5 mm/s, the bonding porcelain layers were still incomplete sintered and there were some micro-cracks in the porcelain. When the laser scanning speed decreased to 7.5 mm/s, vitrified bonding porcelain layers with few pores were synthesized on Ti. [ABSTRACT FROM AUTHOR]

Bioglass coatings derived from electrophoretic deposition method were fused on Ti surface by laser cladding process using a continuous CO 2 laser. The specimens were studied by field-emission scanning electron microscopy, X-ray diffraction and bonding tests. Titanium oxide layer with hierarchical structures consisting of submicron rows of leaf-like embossments and nano-pores was obtained by combining acid etching and anodization processes, which increased the surface roughness of Ti. When heat-treatment temperature was 700 °C and high, CaSiO 3 phase began to crystallize from the bioglass matrix and the crystallinity reached its maximum at 700 °C. During the electrophoretic deposition process, porous bioglass coatings composed of bioglass particles and fibers were deposited on Ti surface. Bioglass coatings with similar hierarchical structure containing submillimeter bioglass beads and microfibers were synthesized on Ti surface by laser fusion. There are no obvious microcracks at the interface of the Ti-coating, which revealed the good bonding between Ti-porcelain. With the laser scanning distance decreased, the bond strength increased accordingly. After only one day immersion in SBF, calcium phosphate began to precipitate on the bioglass coatings' surfaces. The thickness of the calcium phosphate precipitation and the amount of microparticles increased with immersion time. [ABSTRACT FROM AUTHOR]

The use of cardiovascular stents for rapid in vivo re-endothelialization is a promising strategy for reducing cardiovascular implantation or preventing local thrombus formation and restenosis. Surface-patterned intravascular endoprosthetic stents have been developed to prevent life-threatening complications. In this study, vascular smooth muscle cell (VSMC)-biomimetic surface patterns were fabricated on 316L cardiovascular stents using a femtosecond laser and then implanted into the iliac artery of rabbit. The in vitro data revealed that the bionic surface patterns matched the morphology of the VSMCs well, which promotes the adhesion, proliferation, and migration of human umbilical vein endothelial cells. In addition, the patterned surfaces can significantly enhance re-endothelialization. Consequently, the surface biomimetic stent with the VSMC surface pattern is likely an effective approach to ensure rapid re-endothelialization and possibly reduce the incidence of in-stent restenosis. [ABSTRACT FROM AUTHOR]

Surface modifications of Ti and nano-composite coatings were employed to simultaneously improve the surface roughness, corrosion resistance and chemical bonding between porclain-Ti. The specimens were studied by field-emission scanning electron microscopy, surface roughness, differential scanning calorimetry, Fourier transform infrared spectroscopy, corrosion resistance and bonding strength tests. The SEM results showed that hybrid structures with micro-stripes, nano-pores and nano-protuberances were prepared by surface modification of Ti, which significantly enhanced the surface roughness and corrosion resistance of Ti. Porous nano-composite coatings were synthesized on Ti anodized with pre-treatment in 40% HF acid. TiO 2 nanoparticles were added into the hybrid coating to increase the solid phase content of the sols and avoid the formation of microcracks. With the TiO 2 content increasing from 45 wt% to 60 wt%, the quantities of the microcracks on the coating surface gradually decreased. The optimal TiO 2 content for the nanocomposite coatings is 60 wt% in this research. Compared to the uncoated group, the bonding strength of the coated groups showed a bonding strength improvement of 23.96%. The cytotoxicity of the 4# coating group was ranked as zero, which corresponds to non-cytotoxicity. [ABSTRACT FROM AUTHOR]

Silver containing hybrid coatings were synthesized on titanium by sol–gel process. The specimens were studied by transmission electron microscopy, field-emission scanning electron microscopy, bonding test and bacterial counting method. The solid phase content of the sols was increased by the addition of TiO 2 nanoparticles, which avoided the formation of microcracks on the coatings surface. The bonding strength of the coated groups showed a bonding strength improvement of 10.6% compared to the uncoated group. The percent reduction in bacterial count against Staphylococcus aureus seeded on silver containing hybrid coating surface was approximately 99.3% after 24 h incubation, which indicated the strong antibacterial activity of the coating. [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]

Micropatterns which can be controlled precisely were obtained on titanium (Ti) surface by femtosecond lasers (FSL) ablation. The in-situ deposition of bioactive calcium phosphate (Ca/P) phase and collagen hybrid was achieved on Ti surface to form filamentous structure combined with nanoparticles, during the FSL treatment. The amount of deposited Ca/P phase increased with the laser energy during the whole process. While for the deposited collagen amount, it increased with the rise of the laser energy initially, and then decreased with the increase of laser energy. The FSL induced micropatterns and in-situ deposition of Ca/P phase and collagen are expected to result in excellent bioactivity and biocompatibility of the Ti implant. [ABSTRACT FROM AUTHOR]

An excellent hydrophobic and super-oleophilic surface on 316 L stainless steel was obtained by femtosecond laser irradiation in deionized water. Using lower laser fluence and scanning speed of femtosecond laser irradiation, a single stripe structure was fabricated and the corresponding contact angle to water and ethylene glycol was 127.2° and 19.6°, respectively. When laser fluence and scanning speeds increased, stripes, grooves, and holes structures were obtained on the surface and the corresponding water contact angles increased and ethylene glycol contact angles decreased, with a maximum water contact angle of 142.5° and minimum ethylene glycol contact angle of 6.4°. [ABSTRACT FROM AUTHOR]

Highlights: [•] An approach to prepare CNTs-Al2O3 mixture reinforced Mg composite was proposed. [•] CNTs were homogeneously dispersed in Mg matrix with the help of alumina ‘vehicles’. [•] CNTs-Al2O3 reinforced Mg composites show obviously improved mechanical properties. [ABSTRACT FROM AUTHOR]

Oxygen-deficient title compounds with 0 ≤ δ ≤ 0.35 are synthesized from stoichiometric amounts of LaAs, ZnO, and Zn (belt-type high-pressure apparatus, Au capsule, Ar, 6 GPa, 1300 °C, 2 h). [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanotubes (CNTs) with diverse structures (tubular and herringbone) reinforced Al matrix composites were fabricated by a combination of in situ growth process of CNTs in Al powders and powder metallurgy (PM) process. The enhancement efficiency of CNTs with different structures and the interfacial phenomenon between CNTs and Al matrix were investigated. The results showed that herringbone CNTs with more defects reacted with Al matrix slightly and a thin intermediate layer (Al4C3) of about 1–4nm was formed between herringbone CNTs and Al matrix. Nevertheless, the interface between tubular CNTs and Al matrix was close-knit and no obvious transition layer (new phase) was found. The mechanical performance of the composites indicated that the enhancement efficiency of herringbone CNTs in Al matrix composites was lower than that of tubular CNTs, due to the formation of the brittle intermediate layer of Al4C3, implying that tubular CNTs should be more suitable to reinforce Al matrix composite. [Copyright &y& Elsevier]

Abstract: Biocompatibility of the micro-patterned NiTi surface produced by femtosecond laser (FSL) was studied in this work. The surface characteristics of the laser treated NiTi alloys were investigated by scanning electron microscopy (SEM), atom force microscopy (AFM), X-ray diffractometry (XRD) and X-ray photoelectron spectrum (XPS). The biocompatibility was evaluated by in vitro cell culture test. The results showed that, grooves, ripples, which covered by nanoparticles were formed on the sample surfaces, and the Ni/Ti ratio on the alloy surface increased with increasing laser energy. The crystal structure was not changed by laser treatment. However, the cell culture test proved that the micro-patterns induced by FSL were beneficial to improve the biocompatibility of NiTi alloys: the growth of osteoblasts oriented along the grooves, a large amount of synapses and filopodias were formed due to the ripples, holes and nanoparticles on the alloy surface, and the proliferation rate and alkaline phosphatase (ALP) content of cells were increased after FSL treatment. However, due to the toxicity of Ni ions on cell growth, the NiTi alloy surface should not be treated by laser fluence of more than 3.82J/cm2 to obtain the ideal biocompatibility. [Copyright &y& Elsevier]

Abstract: CaO–SiO2 based ceramics have been regarded as potential candidates for artificial bone due to their excellent bone bioactivity and biocompatibility. However, they cannot be used as implants under a heavy load because of their poor mechanical properties, in particular low fracture toughness. Plasma spraying CaO–SiO2 based ceramic coatings onto titanium alloys can expand their application to the hard tissue replacement under a heavy load. Plasma sprayed wollastonite, dicalcium silicate and diopside coatings have excellent bone bioactivity and high bonding strength to titanium alloys. It is possible that these plasma sprayed CaO–SiO2 based ceramic coatings will be applied in clinic after they are widely and systematically researched. [Copyright &y& Elsevier]

Abstract: The effects of nano-porous film synthesized on titanium by anodization processes on the titanium–porcelain bonding were investigated. The morphologies of the films were studied by field-emission scanning electron microscopy (F-SEM). The adhesion between the Ti and porcelain was evaluated by three point flexure bonding test. The corrosion durability of titanium–porcelain bonding strength in artificial saliva with different pH and fluoride concentrations was investigated. The SEM results showed that a titanium oxide film with nano-pores could be prepared on the titanium surface by anodization. This process increased chemical bonding and mechanical interlocking between titanium and porcelain enhancing the corrosion durability of the Ti–porcelain bonding strength. [Copyright &y& Elsevier]

Novel Mg–graphene-nanoplatelet (GNP) composites were fabricated using the Rieke method to synthesize Mg in situ on the GNP surfaces and powder metallurgy (PM). Mg particles synthesized using the Rieke method were deposited on the surfaces of the GNPs during the displacement reaction between Li and anhydrous MgCl 2 , which yielded in situ Mg-encapsulated GNPs (GNPs@Mg) composite structures. In the GNPs@Mg composite structures, the displaced Mg was closely attached to the surfaces of the GNPs in a nanocrystallite form and achieved a close mechanical interfacial bonding with the GNPs. After employing the PM, the obtained GNPs@Mg composite powders were transformed into GNPs@Mg bulk composites, which ensured the integrity and dispersion of the GNPs in the Mg matrix. The mechanical properties of the GNPs@Mg bulk composite were significantly improved owing to the strengthening effects of the GNPs. The yield strength and ultimate tensile strength of a 1.5-wt.% GNPs@Mg bulk composite were approximately 38.8 and 35.1% higher than those of a pure Mg bulk, respectively, while the hardness and elongation to failure were increased by approximately 47.4 and 36.5%, respectively. Furthermore, the strengthening and toughening efficiencies of the GNPs@Mg bulk composites were significantly higher than those of GNPs/Mg composites fabricated using the conventional addition method. Therefore, this research provides new insights into the process design of high-performance lightweight structural metallic materials. Image 1 • Novel GNPs@Mg composites were fabricated using in situ displacement and PM methods. • Synthesized Mg heterogeneously nucleates and grows on GNPs to form GNPs@Mg structure. • GNPs as nucleation sites of Mg effectively refine the size of Mg crystal grains. • Nanoscale contact and mechanical occlusion of GNP–Mg improves interfacial bonding. • The mechanical properties of GNPs@Mg composites were significantly improved. [ABSTRACT FROM AUTHOR]