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Objective: Recently, stainless steel (SSL) miniscrew implants have been used in orthodontic clinics as temporary anchorage devices. Although they have excellent physical properties, their biocompatibility is relatively poor. Previously, our group developed a two-phase biomimetic calcium phosphate (BioCaP) coating that can significantly improve the biocompatibility of medical devices. This study aimed to improve the biocompatibility of SSL by coating SSL surface with the BioCaP coating. Methods: Titanium (Ti) discs and SSL discs (diameter: 5 mm, thickness: 1 mm) were used in this study. To form an amorphous layer, the Ti discs were immersed in a biomimetic modified Tyrode solution (BMT) for 24 h. The SSL discs were immersed in the same solution for 0 h, 12 h, 24 h, 36 h and 48 h. To form a crystalline layer, the discs were then immersed in a supersaturated calcium phosphate solution (CPS) for 48 h. The surface properties of the BioCaP coatings were analysed. In addition, bovine serum albumin (BSA) was incorporated into the crystalline layer during biomimetic mineralisation as a model protein. Results: The morphology, chemical composition and drug loading capacity of the BioCaP coating on smooth SSL were confirmed. This coating improved roughness and wettability of SSL surface. In vitro, with the extension of BMT coating period, the cell seeding efficiency, cell spreading area and cell proliferation on the BioCaP coating were increased. Significance: These in vitro results show that the BioCaP coating can improve surface properties of smooth medical grade SSL and serve as a carrier system for bioactive agents.

Item does not contain fulltext Implant-supported dental prosthetics are widely used in dental practice. Sufficient peri-implant bone tissue is a crucial prerequisite for the long-term success of this treatment, as insufficient peri-implant bone volume hampers dental implant installation and negatively influences dental implant stability. However, due to tooth extraction, bone metabolism diseases, and trauma, bone defects in the jaw are common in patients, particularly in the elderly and those suffering from underlying conditions. If this is the case, the alveolar ridge has to be augmented for reliable implant placement. Various biomaterials, growth factors (GFs) or GF-based products, and trace elements have been tested and used for alveolar ridge augmentation. Among those biomaterials, calcium phosphates (CaPs) are the most popular due to their promising biocompatibility, great osteoconductivity, and distinguishing osteogenesis. Combining CaPs with GFs or trace elements can further favor bone defect repair. This review mainly focuses on applying artificial CaP biomaterials and their combination with bioactive agents to repair bone defects in implant dentistry.

Hypophosphatasia is a rare metabolic inherited dento-osseous disorder. Although there is some available literature on various dental characteristics of hypophosphatasia patients, few reports focus on the effects of hypophosphatasia on the permanent dentition and prosthodontic rehabilitation, particularly in relation to the use of dental implants. This paper reports a case with hypophosphatasia and prosthodontic rehabilitation using dental implants with 7-year follow-up.

In order to evaluate loading methods and the dose dependency of bone morphogenetic protein 2 (BMP-2) in ectopic bone formation, an osteoinductive material consisting of commercially available coralline hydroxyapatite (CHA) was coated with a layer of biomimetic calcium phosphate (BioCaP) containing BMP-2 in different ways. Eight groups—each containing samples of 0.25 g CHA—were formed and coated with, respectively, BioCaP with internally incorporated BMP-2 in concentrations of 1, 5, 10, 20, 40 and 60 µg per sample, and the two control groups with BioCaP only and BioCaP with 20 µg of adsorbed BMP-2 per sample. The samples were implanted subcutaneously in 27 male Wistar rats. The histological results show that there is no bone formation in the group in which no BMP-2 was included. All samples with BioCaP containing BMP-2 show bone formation. The group with 20 µg of adsorbed BMP-2 per sample shows the least bone formation. Coating-incorporated BMP-2 is more efficient in inducing bone formation than adsorbed BMP-2. The group with 5 µg of coating-incorporated BMP-2 per sample shows the most bone formation. Increasing the amount of coating-incorporated BMP-2 up to 60 µg does not improve ectopic bone formation.

The aim of this study is to investigate the efficacy and the effect of the dosage of the slow-released Escherichia coli-derived recombinant human bone morphogenetic protein 2 (ErhBMP-2) functionalized β-tricalcium phosphate (β-TCP) in repairing critical-sized bone defects. The functionalization was implemented by modifying the surface of β-TCP with biomimetic calcium phosphate coating with or without ErhBMP-2. Critical-sized calvarial defects were created in rats and filled with ErhBMP-2 functionalized β-TCP loaded with gradient doses of ErhBMP-2 (0, 50, 100, 150, 200, and 300 μg/g). The blank control group and the autologous bone group were also included. The systemic toxicity was evaluated using routine blood and histopathological examination. The efficiency in bone healing was evaluated using microcomputed tomography, histology, and histometric analyses. Neither local nor systemic adverse effects were found following the implantation of the ErhBMP-2 functionalized β-TCP. The new bone formation was significantly increased in the ErhBMP-2 functionalized β-TCP groups compared with the blank group and the β-TCP with coating only group. The efficacy of the ErhBMP-2 functionalized β-TCP in bone healing was comparable to that of the autologous bone. There was no significant difference in bone formation among all concentrations of ErhBMP-2 (0-300 μg/g). Increased bone maturation was found in the higher concentration groups (150, 200, and 300 μg/g) when compared with the lower concentration groups (50, and 100 μg/g). Our results demonstrated that the ErhBMP-2 functionalized β-TCP could significantly promote bone repairing in critical-sized defects, and it could clinically be a promising substitute for autologous bone. Besides, our results demonstrated that there was a dosage-dependent effect of ErhBMP-2 functionalized β-TCP on bone maturation rather than bone formation. The optimized concentrations of ErhBMP-2 recommended for this kind of model should be in the range of 150-300 μg/g. Bone substitutes functionalized by mammalian-derived recombinant human bone morphogenetic protein 2 (rhBMP-2) have demonstrated to be comparable to the autologous bone in repairing the critical-sized bone defects. To develop a commercial product with more effective cost, Escherichia coli-derived rhBMP-2 (ErhBMP-2) has been produced and evaluated as an alternative to the mammalian-derived rhBMP-2. In this study, we prepared gradient ErhBMP-2 functionalized β-tricalcium phosphate (β-TCP) with biomimetic calcium phosphate coating and investigate their efficacy and dose effects. We revealed the dose effects of the slow-released ErhBMP-2 and demonstrated that ErhBMP-2 functionalized β-TCP could be a promising bone substitute for bone regeneration in clinical settings.

Aim: To evaluate the effect of bone morphogenetic protein 2 (BMP-2) incorporated biomimetic calcium phosphate (BMP-2/BioCaP) in conjunction with barrier membrane on periodontal regeneration in chronic periodontitis experimental model. Material and Methods: Chronic periodontitis experimental model with critical-sized supra-alveolar defects was created in 15 dogs’ mandibles. After the initial periodontal therapy, the defects were randomly assigned to the following groups: (a) control; (b) barrier membrane; (c) deproteinized bovine bone mineral + barrier membrane; (d) BioCaP + barrier membrane and (e) BMP-2/BioCaP + barrier membrane (6 quadrants with 18 teeth per group). Eight weeks later, clinical examinations, micro-CT, and histomorphometric analyses were performed. Results: Clinical examinations, including plaque index, bleeding index, and probing depth, were similar for all groups. In contrast, the clinical attachment loss was significantly lower in defects grafted with BMP-2/BioCaP and barrier membrane. The micro-CT results showed that the height of mineralized tissue in defects grafted with BMP-2/BioCaP and barrier membrane was significantly higher. For histometric analysis, the defects grafted with BMP-2/BioCaP and barrier membrane exhibited significantly more connective tissue height, new cementum height, new bone height and area, as well as less down-growth of junctional epithelium. Conclusion: BMP-2/BioCaP could be a promising bone substitute for periodontal regeneration.

p-Type transparent conducting materials (p-TCMs) are important components of optoelectronic devices including solar cells, photodetectors, displays, and flexible sensors. Cu–Zn–S thin films prepare...

Appropriate dispersion of cocatalyst on semiconductor for improving photocatalytic H2 production efficiency is a challenging work in semiconductor photocatalysis. Herein, we constructed the noble-metal-free CoSx modified tubular sulfur doped carbon nitride (SCN) photocatalysts by chemical precipitation process. The amorphous CoSx well dispersed on SCN served as H2 production sites, which reduced the overpotential and inhibited the recombination of photogenerated carriers by interfacial charge transfer. Maximized H2 production rate of 573.06 μmol g−1 h−1 under visible light irradiation was obtained by optimizing the CoSx loading proportion to 2.4%, which was higher than that of 0.75 wt% Pt/SCN. In addition, a possible mechanism for improved H2 production activity was proposed based on the experiments and discussion. This work provides a new strategy to design rational structure of non-noble metal cocatalyst modified photocatalyst to further improve H2 production performance.

Graphitic carbon nitride is considered as one of the promising photocatalysts for pollution elimination from wastewater. Manipulating the microstructure of carbon nitride remains a challengeable task, which is essential for improving light absorption, separating photogenerated carrier and creating reactive sites. Herein, a carbon vacancy modified hierarchical carbon nitride microrod (CN1.5) has been prepared templated from a melamine-NH2OH·HCl complex. The hierarchical microrods are demonstrated to be comprised of interconnected nanosheets with rich carbon vacancies, which endows it with high specific surface area, enhanced light utilization efficiency, available reactive sites, improved charge carrier separation and numerous mass-transport channels. The resultant photocatalyst CN1.5 exhibits an excellent photodegradation efficiency of 87.9% towards tetracycline under visible light irradiation. The remarkable apparent rate constant of 4.91 × 10−2 min−1 is 7.3 times higher than that of bulk CN. In addition, the degradation pathways are deduced base on the observation of degradation intermediates generating in the photocatalytic process. Mechanism investigation indicates that the major contribution for photodegradation is attributed to ·O2–, 1O2 and H2O2 species. This work provides new insights into advancing carbon nitride's microstructure to improve photocatalytic degradation performance for highly efficient antibiotic removal and environment remediation.

Correction for ‘Strontium-incorporated mesoporous bioactive glass scaffolds stimulating in vitro proliferation and differentiation of bone marrow stromal cells and in vivo regeneration of osteoporotic bone defects’ by Yufeng Zhang et al., J. Mater. Chem. B, 2013, 1, 5711–5722.

Objective: We hypothesized that a biomimetic calcium phosphate (CaP) coating which incorporates morphogenetic protein 2 (BMP-2) on the deproteinized bovine bone (DBB) blocks could be used to enhance the vertical alveolar ridge augmentation for the one-stage onlay surgery with simultaneous implants insertion. We aimed to test this hypothesis in vivo. Material and methods: Beagles dogs were used for the study (n = 6 specimens per group). One month after building the edentulous animal model, 4 mm vertical alveolar bone loss were surgically created and four groups of blocks (W × L × H: 7 mm × 10 mm × 4 mm) were randomly fixed onto the reduced alveolar ridge by implants: (a) DBB blocks alone (negative control group); (b) DBB blocks with superficial adsorption of 50 μg BMP-2 (ad.BMP-2 group); (c) DBB blocks coated by biomimetic CaP coating which incorporates 50 μg BMP-2 (inc.BMP-2 group); and (d) autologous bone blocks (positive control group). After 3 months of healing, samples were harvested for micro-CT and histomorphometric analyses. Results: In histomorphometry, the inc.BMP-2 group showed a significantly thicker (coronal-apically) and wider (buccal-lingually) augmented bone area, better bone-to-implant contact than the negative control group. In both the micro-CT and histomorphometry, the inc.BMP-2 group showed more mineralized tissue than the negative control group and the inc.BMP-2 group also showed significantly more newly formed bone and residual grafts than the negative control group in the upper half of the blocks. In micro-CT, the inc.BMP-2 group showed significantly more bone-to-graft contact percentage than the ad.BMP-2 group. In both micro-CT and histomorphometry, the inc.BMP-2 group showed significantly more percentage of mineralized tissue than the ad.BMP-2 group. No significant differences were found between the inc.BMP-2 group and the positive control group either in micro-CT or in histomorphometry. Conclusions: The DBB blocks with coating-delivered BMP-2 significantly enhanced the efficacy of vertical alveolar bone augmentation, compared with the unloaded blocks and blocks with adsorbed BMP-2, in the one-stage onlay surgery with simultaneous implant insertion.

A series of visible-light-active NH2-MIL-125/TiO2/CdS yolk–shell and hollow H-TiO2/CdS hybrid heterostructures were successfully synthesized via the hydrolysis of NH2-MIL-125 metal–organic framework (MOF) using thioacetamide (CH3CSNH2) and cadmium acetate (Cd (CH3COO)2·2H2O) by the post solvothermal method, after which the obtained heterostructures were applied to H2 photocatalytic production. Among the yolk–shell and hollow heterostructures, NH2-MIL-125/TiO2/CdS (30) and H-TiO2/CdS (30) exhibited the highest H2 production activity of 2997.482 and 1970. 813 μmol g–1 h–1, with the apparent quantum efficiency of 4.81% and 2.41% at 420 nm, respectively. These superior photocatalytic performances of the heterostructures could be due to the strong interaction of the component based on intimate contact, large surface area, and porous structures that assisted the mass transfer, thereby forming abundant reactive sites. Moreover, the introduction of CdS nanoparticles into the MOF derivatives enhanced the visible l...

Background and objective Periodontitis is a chronic inflammatory disease characterized by the destruction of the periodontium. The strontium ion (Sr2+ ) can prevent the bone loss associated with periodontitis and promote the regeneration of the bone. The mechanisms by which the Sr2+ works remain poorly understood. We aim to investigate the effects of the Sr2+ ion on cell proliferation, inflammatory regulation and osteogenic differentiation of human periodontal ligament cells (hPDLCs) in pathological conditions. Material and methods hPDLCs were obtained from premolars that came from the orthodontic extraction. The hPDLCs were treated with Sr2+ and/or lipopolysaccharide (LPS), which was applied as the pathological condition of periodontitis. The effect of the dose of Sr2+ on cell proliferation was analyzed using a Cell Counting Kit-8 assay. The gene and protein expression of proinflammatory cytokines were detected by the real-time polymerase chain reaction and enzyme-linked immunosorbent assay. The osteogenic differentiation and mineralization were assessed by the real-time polymerase chain reaction, alkaline phosphatase activity assay and alizarin red staining. Results Results demonstrated that Sr2+ in a range of concentrations from 0.02 to 2.5 mmol/L significantly improved the proliferation of hPDLCs. Sr2+ reversed LPS-stimulated proinflammatory cytokine expressions such as tumor necrosis factor alpha, interleukin (IL)-1β, IL-6 and IL-8. Moreover, Sr2+ rescued the LPS-inhibited gene expression of osteogenic differentiation. Although it appeared to suppress the late mineralization, Sr2+ can reverse the LPS-inhibited early osteogenic differentiation of hPDLCs. Conclusion These results indicated that Sr2+ could attenuate the LPS-stimulated proinflammatory molecule expression and inhibit early osteogenic differentiation of hPDLCs.

This work studied a facile and template-free hydrothermal route for controlled synthesis of tungsten trioxide in the form of hexagonal nanorod (h-WO3) and monoclinic nanosheet (m-WO3). The surface morphology, crystal plane, surface bound water, and surface acid sites of the two kinds of WO3 nanocrystals were investigated systematically. They were further evaluated as catalysts for selective cellulose hydrolysis. While both of them exhibited good catalytic performance, h-WO3 was found to be more preferential for ethylene glycol (EG) generation. This catalytic performance relied on both the unique active crystal surface (1 0 0) and surface binding water (WO3-H2O) formed by h-WO3 crystals, which provided more Lewis acid sites for degrading cellulose into EG. Results showed that the highest EG yield reaches 77.5% by a combination of loading 1 wt% Ru on the h-WO3 catalyst.

Different amount of boron-modified Ni/Mo2C were synthesized, characterized and tested during the hydrogenation of alkali lignin, to evaluate the effect of boron on the Ni promoted behavior. xB–Ni/Mo2C (x = 0.5, 1, 3, 5) is found to enhance the lignin conversion and bio-oil yield at the same time, and the highest bio-oil yield was obtained with 1B–Ni/Mo2C (63.8%), under the optimum reaction condition (2 MPa H2, 290 °C and 2 h). Characteristic results of BET method, ICP-OES, XRD, Raman, SEM, TEM, XPS, H2-TPR and NH3/CO2/CO-TPD indicate the improved catalytic performance comes from strong interaction between boron and nickel species, which results in improved surace area, highly dispersed Ni particles, increased acidic sites, thus favors cleavage of the C–O and C–C bonds. A possible reaction mechanism was also present based on the catalytic system.

We report a simple and efficient method for the preparation of highly dispersed Au nanoparticles (

A series of Ni/CeO2 catalysts were synthesized via a simple one-pot hydrothermal method and characterized by XRD, SEM, TEM, EDX, EDX mapping, Raman, H2-TPR, BET, XPS, TGA and ICP-MS. Their catalytic performances were systematically evaluated in hydroliquefaction of rice straw. The impact of reaction temperature, reaction time, H2 pressure and Ni/Ce molar ratios on product yields and distribution was also investigated. The conversion (89.08%) of rice straw and bio-oil yield (66.7%) obtained over Ni/CeO2 catalyst with a Ni/Ce molar ratio of 2/10 are superior to those over no catalyst (conversion of 73.65%, bio-oil yield of 47.96%) and pure CeO2 catalyst (conversion of 77.79%, bio-oil yield of 56.67%) under the optimum condition (290 °C, 1.0 h, and 2.0 MPa H2 pressure). GC–MS results show that the main components of bio-oil are phenols, which are high-value-added, important and useful chemicals in transportation and chemical industries. It is worth noting that the highly dispersed Ni nanoparticles and their stronger interaction between Ni and CeO2 with more oxygen vacancies facilitate high conversion of rice straw and bio-oil yield. In addition, a possible catalytic mechanism of Ni/CeO2 catalyst for hydrogenation of rice straw is accordingly proposed. This work thus offers an effective approach to improve the conversion of rice straw and bio-oil yield over Ni/CeO2 catalysts.

Metal–organic framework (MOFs) based composites have received more research interest for photocatalytic applications during recent years. In this work, a highly active, visible light photocatalyst BiOBr/UiO-66-NH2 hybrid composite was successfully prepared by introducing various amounts of UiO-66-NH2 with BiOBr through a co-precipitation method. The composites were applied for the photocatalytic degradation of RhB (rhodamine B) dye. The developed BiOBr/UiO-66-NH2 composites exhibited higher photocatalytic activity than the pristine material. In RhB degradation experiments the hybrid composite with 15 wt% of UiO-66-NH2 shows degradation efficiency conversion of 83% within two hours under visible light irradiation. The high photodegradation efficiency of BUN-15 could be ascribed to efficient interfacial charge transfer at the heterojunction and the synergistic effect between BiOBr/UiO-66-NH2. In addition, an active species trapping experiment confirmed that photo-generated hole+ and O2− radicals are the major species involved in RhB degradation under visible light.

Hydrogenolysis of glycerol has been a subject of intensive research in recent decades. Great efforts have been made investigating the mechanism of bond cleavage using metal or metallic oxide catalysts. In this work, effects of a series of WCx-based catalysts, including WCx, Cu/WCx, Pt/WCx, Ru/WCx, CuRu/WCx and CuPt/WCx, were studied on hydrogenolysis of glycerol to investigate the role of each active phase. WO3-Based catalysts were employed as a comparison with the WCx-based catalysts. Hydrogenolysis of model compounds (1,2-PDO and EG) of glycerol was also studied using these catalysts, in attempts to determine the mechanism of the whole reaction. The presence of metal elements on WCx or WO3 can significantly improve the conversion of reactant. In addition, the ability of WCx to promote cleavage of C–C was verified. Ru is more beneficial for formation of EG than Pt, whereas Pt is favorable for formation of 1,2-PDO. It had been supposed that hydrogenolysis of glycerol by WCx-based catalysts occurred via two different but overlapping routes: WCx-related reactions caused by C–C cleavage and metal-related reactions caused by C–O cleavage, which happen simultaneously in the reaction. The current study not only demonstrates that the catalytic performance of WCx can be manipulated by varying metal loading, but also offers a possible mechanism for C–C and C–O cleavage in hydrogenolysis of glycerol, which could be beneficial when focusing on the target product.

Stereolithographic 3D printing has been increasingly applied in the rapid fabrication of gels with specially-designed 3D structures. Herein, MXene (Ti3C2Tx) is reported for the first time as a versatile photo blocker for a photo-curable aqueous ink for a newly developed stereolithography technology (Continuous Liquid Interface Production, CLIP) to fabricate hydrogels with delicate geometries. As an effective photo blocker, the MXene nanosheets can significantly suppress the light scatting in the hydrogel precursor ink during CLIP printing, giving rise to printing quality. Subsequent solvent exchange with glycerin produces an organogel, which shows excellent adhesive properties towards various surfaces, making it a promising adhesive sensor to detect different body movements. Meanwhile, the CLIP-printed organogel demonstrates promise in atmospheric water harvesting taking advantage of the natural hygroscopicity of organogel and excellent light-to-heat conversion performance with MXene nanosheets. Furthermore, the CLIP-printed hollow organogel shows higher efficiency benefiting from larger surface area of hollow organogel. The results of this work strongly suggest that MXene can serve as an effective multifunctional additive for CLIP inks, which may open up new opportunities for the 3D printing of various advanced devices.

This paper describes catalytic hydrogenation liquefaction of rice straw over metal (Ni, Co, and Cu)-modified CeO2 catalysts for bio-oil production. The results show that the highest rice straw conversion (89.08%) and bio-oil yield (66.7%) were obtained over Ni/CeO2 catalyst. The bio-oil contains mainly phenols, high-value-added, and widely used chemicals. Furthermore, metal-modified CeO2 catalysts can significantly influence the components of bio-oil with the highest percentage of C7-C10 compounds. This work thus demonstrates that metal/CeO2 catalysts can be effective in improving the bio-oil yield and selectivity in hydro-liquefaction of rice straw into bio-oil.

A series of Ce-doped TiO2 nanoparticles were prepared by a sol–gel process and characterized by XRD, SEM, TEM, EDX mapping, UV–vis DRS, Raman spectroscopy, N2 adsorption–desorption, PL spectra, CO2-TPD, and XPS. It is found that Ce ions can enter the lattice matrix of TiO2 and occupy of Ti sites. This atom replacement leads to the formation of impurity energy levels in the band gap of TiO2, extending light absorption into the visible light region. Because Ce has a more flexible valence state, both Ce3+ and Ce4+ could be formed in the composites. The preference facilitates the photoinduced charge separation inside of the crystals. Moreover, Pd nanoparticles were then loaded as a co-catalyst on the surface of doped composites. As the trapping center of electrons, it can efficiently adsorb and activate CO2 molecules, promoting their transformation into CH4. These composites were then evaluated as photocatalysts for CO2 hydrogenation. While all of them could efficiently catalyze the reaction, 1.0% Pd/0.5% Ce-...

Titanium-based metal–organic frameworks (MOFs), named MIL-125 and NH2-MIL-125, have been successfully synthesized by the hydrothermal method. They were specially designed for the application of methylene blue (MB) removal from aqueous solution. The maximum adsorption capacity of MB was found to be 321.39 mg/g and 405.61 mg/g. The amount of dye that has been adsorbed 99.9% was 300 ppm within 20 and 120 intervals of time. The results show that NH2-MIL-125 is more effective in terms of both selectivity and capacity for the adsorption of MB cationic dye compared with MIL-125. The high adsorption selectivity was due to the unique electrostatic interaction between the amino groups of the dye molecules and NH2-MIL-125 but, on the other hand, owing to the more negative zeta potential (−32.4 mV), resulted from the charge balance for the protonation of −NH2. Moreover, reaction parameters including exposure time, adsorbent dose (0.02–0.05 mg), initial dye concentration (100–500 mg/L), and temperature were studied in...

We fabricate a novel cellulose acetate (CA) ultrafiltration membrane modified by block copolymer F127-b- PDMAEMA, which is synthesized using F127 and DMAEMA via the ARGET ATRP method. Compared to conventional ultrafiltration membranes, the incorporation of both F127 and PDMAEMA can not only readily increase the hydrophilicity of the membrane, but also exhibit stimuli-responsiveness to temperature and pH. Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (NMR), and gel permeation chromatography (GPC) are employed to analyze the structure of the F127-b-PDMAEMA. The membrane properties are evaluated via scanning electron microscope (SEM) imaging, porosity test, automatic target recognition Fourier transform infrared spectroscopy (ATR-FTIR), water contact angle test and permeation test. The results indicate that the F127-b-PDMAEMA is an excellent pore agent, which contributes to an enhancement of the membrane in sensitivity to temperature and pH. The modified membrane also exhibits lower water contact angle (64.5°), which is attributed to the good anti-fouling performance and high water permeation.

p-Type transparent conducting materials (p-TCMs) are important components of optoelectronic devices including solar cells, photodetectors, displays, and flexible sensors. Cu-Zn-S thin films prepared by chemical bath deposition (CBD) can have both high transparency in the visible range (>80%) as well as excellent hole conductivity (>1000 S cm-1). However, the interplay between the deposition parameters in the CBD process (metal and sulfur precursor concentrations, temperature, pH, complexing agents, etc.) creates a multidimensional parameter space such that optimization for a specific application is challenging and time-consuming. Here we show that strategic design of experiment combined with machine learning (ML) allows for the efficient optimization of p-TCM performance. The approach is guided by a figure of merit (FOM) calculated from the film conductivity and optical transmission in the desired spectral range. A specific example is shown using two steps of optimization using a selected subset of four experimental CBD factors. The ML model is based on support vector regression employing a radial basis function as the kernel function. 10-fold cross-validation was performed to mitigate overfitting. After the first round of optimization, predicted areas in the parameter space with maximal FOMs were selected for a second round of optimization. Films with optimal FOMs were incorporated into heterojunction solar cells and transparent photodiodes. The optimization approach shown here will be generally applicable to any materials synthesis process with multiple parameters.

In the present work, CdS nanoparticles were integrated into sodium alginate aerogel matrix through a facile method. The CdS particles were successfully incorporated into the network of sodium alginate and highly distributed. Moreover, the accessibility of pore structures of sodium alginate was well-preserved. The resulting hybrid aerogels demonstrated high photocatalytic ability towards Cr (VI) reduction. SA/CdS-2 (mass ratio SA: CdS = 1:2) exhibited the highest reduction efficiency of Cr (VI), which could reduce the concentration of Cr (VI) to 0 mg/L after 60 min illumination. A probably adsorption-photoreduction mechanism was proposed and discussed in detail. The aerogels had excellent reusability and recyclability, avoiding secondary pollution. This work holds a promise to design and fabrication of CdS particles into three-dimensional aerogel network.

The delivery of novel bioactive scaffolds for the repair of bone defects remains a prominent challenge worldwide. Currently osteoporosis, a disease caused by low bone mineral density affects over 200 million people worldwide with up to half of this population experiencing at least one fracture within their lifetime. Recently temperature-sensitive p(N-isopropylacrylamide-co-butyl methylacrylate) nanogel (PIB nanogel) scaffolds have emerged as biomaterial candidate for regenerative therapies. It has the advantage of being injected from syringes as a soluble gel form (capable of delivering growth and/or living progenitor cells) yet hardens once it reaches body temperatures. Although this material demonstrates optimal clinical delivery of scaffolds, its main drawback is its low osteoconductivity and bioactivity. Recently we have demonstrated that mesoporous bioactive glass (MBG) loaded with strontium was able to regenerate osteoporotic defects in vivo and enhance osteoblast differentiation in vitro. The aim of this study was to combine the advantages of these two therapies and prepare PIB-nanogel scaffolds containing Sr-MBG and investigate their ability to regenerate femur defects created in ovarectamized rats. The results demonstrate that groups containing Sr-MBG within the nanogel formulation had significantly higher new bone formation when compared with other modalities. We further demonstrate that although nanogel demonstrated poor osteogenic ability, the addition of osteoblasts worked synergistically with Sr-MBG particles to enhance the regeneration of the created femur defects in osteoporotic animals. In conclusion, PIB nanogel scaffolds are a viable treatment modality for bone tissue engineering and may serve as a carrier-scaffold for osteogenic cells and/or bioactive scaffolds such as Sr-MBG. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1175-1183, 2017.

Although the conversion of cellulose to polyols is currently well-developed, the production of the considerably valuable ethylene glycol (EG) is still challenging. Reactions have long relied on the design of suitable catalysts to obtain a high selectivity and yield of EG. Herein, using well-shaped rectangular tungsten trioxide nanosheets as the substrate, we investigated the catalytic performances of various metal supported catalysts for the convertion of cellulose to EG. Results show that Ru/WO3 is more favorable for EG production, with the highest EG yield of 76.3% over the 1% Ru/WO3 nanosheet catalyst. Our characterizations and activity tests suggest that the embedding of Ru nanoparticles onto the WO3 nanosheets produces more W5+ active sites under the same reduction conditions (NaBH4 or H2), which act as Lewis base sites to promote the glucose retro-aldol condensation reaction. Moreover, the Ru/WO3 catalyst holds a portion of Ru in the form of amorphous RuOxδ+ phases, which could further increase the H+ released into an aqueous solution for cellulose hydrogenolysis. A possible catalytic mechanism for this hydrogenolysis process is accordingly proposed.

Mesoporous Ce0.4Zr0.6O2 solid solutions with four different shapes, including mixed nanorod and nanoparticle (RP, cubic), nanopolyhedron (PH, tetragonal), nanosphere (SP, cubic) and nanoegg (EG, tetragonal), were hydrothermally fabricated. Various physical and chemical techniques were used to reveal shape-dependent structural, optical, electronic and surface properties, providing a powerful insight into the morphological dependence of photocatalytic activity towards methylene blue (MB) degradation. Among these samples, RP, consisting of a cubic Ce-rich phase (Ce0.6Zr0.4O2 nanorods) and a tetragonal Zr-rich phase (Ce0.2Zr0.8O2 nanoparticles), affords the optimal functionality, with a top degradation rate (D = 70.5%) and a peak rate constant (k = 0.0102 min−1). This occurrence results mainly from the prompt separation of excitons and suitable textural properties for MB absorption and activation. A brief introduction to the reaction path when using RP is proposed.

Given the low price and abundance of alkali lignin from pulp and paper industry, the conversion of alkali lignin into valuable chemicals has been of great significance to address the world energy crisis. In principle, this process has long relied on the design of a functionalized catalyst to enable high reactivity and selectivity. Herein, we present a systematic study on the hydrogenation liquefaction of alkali lignin using a series of flower-like hierarchical MoS 2 –based catalysts, in which, the effect of various reaction parameters, such as temperature, H 2 pressure, and reaction time, on product yield and distribution was evaluated. Catalysts were characterized by Powder X-ray diffraction, transmission electron microscopy and scanning electron microscopy. N 2 adsorption-desorption isotherms, surface area, pore size distributions and the average pore diameter of catalysts were also measured and calculated. It is worth noting that the incorporation of a secondary metal sulfide into MoS 2 could significantly enhance the catalytic performance. Particularly, by using 5 wt% CoS 2 /MoS 2 as catalyst and having H 2 pressure, reaction temperature, and reaction time set to be 2.5 MPa, 310 °C, and 1 h, respectively, the highest conversion of alkali lignin could reach 91.26%, with a bio-oil yield of 86.24%. This work thus offers an effective approach to improve the conversion and selectivity in catalytic hydrogenation of alkali lignin into bio-oil by using MoS 2 –based catalysts.

Statement of problem: Recombinant human bone morphogenetic protein 2 (rhBMP-2) has been introduced to clinical practice because of its osteoinductive capacity. However, the evidence of its efficacy in vertical bone augmentation procedures is not clear. Purpose: The purpose of this systematic review and meta-analysis was to investigate the efficacy of rhBMP-2 in vertical bone augmentation and to establish whether its addition in preclinical experiments (animal studies) would be sufficient to justify further clinical and histometric studies. Material and methods: An electronic search of 3 databases, PubMed/MEDLINE, EMBASE, and Web of Science, and a manual search of the reference list of relevant studies were performed. Only randomized controlled trials regarding animal studies comparing the efficacy of bone grafts supplemented with and without rhBMP-2 in vertical bone augmentation procedures were included and reviewed. Results: Nine studies were included. The results of the meta-analysis showed that the pooled weighted mean difference (WMD) of the percentage of newly formed bone was 9.97% (95% confidence interval [CI]=−0.79% to 20.72%; P=.070), the WMD of the percentage of residual materials was −21.31% (95% CI=−70.62% to 28.00%; P=.400), the WMD of the augmented bone height was 1.70 mm (95% CI=−0.23 to 3.63 mm; P=.080), the WMD of the augmented bone height for studies with space-providing barriers was 1.00 mm (95% CI=0.43 to 1.57 mm; P

Semaphorins have been recently targeted as new molecules directly implicated in the cell-cell communication that occurs between osteoclasts and osteoblasts. Overexpression of certain semaphorins, such as semaphorin4D (sema4D), is found in an osteoporotic phenotype and plays a key role in osteoclast activity by suppressing osteoblast maturation, thus significantly altering the bone modeling cycle. In the present study, we fabricate a site-specific bone-targeting drug-delivery system from polymeric nanoparticles with the incorporation of siRNA interference molecule for sema4D and demonstrate their cellular uptake and intracellular trafficking within osteoclasts, thus preventing the suppression of osteoblast activity. We then demonstrate in an osteoporotic animal model induced by ovariectomy that weekly intravenous injections led to a significantly greater number of active osteoblasts at the bone surface, resulting in higher bone volume in compromised animals. The findings from the present study demonstrate a novel and promising site-specific therapeutic option for the treatment of osteoporosis via interference of the sema4D-plexin cell communication pathway between osteoclasts and osteoblasts. © 2014 American Society for Bone and Mineral Research.

Metal-organic framework (MOFs) based composites have received more research interest for photocatalytic applications during recent years. In this work, a highly active, visible light photocatalyst BiOBr/UiO-66-NH

Background Replacement bone grafting materials are used clinically for a variety of clinical procedures to augment and replace lost or missing bone. Little information is available regarding their degradation properties. Purpose The aim of the present study was to investigate the degradation rate and modes of degradation of four commonly used bone grafting materials. Materials and Methods A natural bone mineral (NBM) of bovine origin, NBM in combination with enamel matrix derivative (EMD), LifeNet demineralized freeze-dried bone allograft (DFDBA), and Osteotech DFDBA were analyzed for particle degradation over time in 3 mm femur defects created in female Wistar rats. At 2, 4, and 8 weeks postimplantation, femur defects were assigned to histological analysis. Hematoxylin and eosin, Safranin O, tartrate-resistant acid phosphatase (TRAP), receptor activator of nuclear factor kappa B ligand (RANKL), and matrix metalloproteinase-2 (MMP-2) staining were performed to determine the rate of particle degradation, number of osteoclasts around particles, and intensity and localization of TRAP, RANKL, and MMP-2 staining. Results In the present study, NBM particles demonstrated little signs of degradation. The combination of NBM with EMD significantly increased the number of osteoclasts around NBM particles and increased expression of RANKL and MMP-2 specifically around particle surface. Only minor resorption was observed. Both DFDBA particles showed much faster degradation of particles. Interestingly, fewer osteoclasts were found on their surface when compared with NBM particles, specifically on Osteotech DFDBA particles, suggesting an alternative mode of degradation. Osteotech DFDBA particles demonstrated significantly faster degradation when compared with all other bone grafts. No obvious increase in TRAP, RANKL, or MMP2 was observed to validate this fast rate of degradation. Conclusions The results from the present study demonstrate a wide range of particle degradation between various commonly commercially available bone grafts. Further research to determine the precise mechanisms that influence particle degradation is necessary.

Objective The purpose of this investigation was to compare the osteoinductive and osteopromotive potential of two widely used demineralized freeze-dried bone allografts (DFDBA) (Osteotech® DFDBA and LifeNet® DFDBA). Material and Methods Twenty-seven male Wistar rats (mean body weight 200 g) were treated with either DFDBA from Osteotech and LifeNet or control for femoral and intramuscular defects and assigned to histological analysis at 2, 4, and 8 weeks postimplantation. Hematoxylin and eosin (H&E), Safranin-O, tartrate-resistant acid phosphatase (TRAP), and osteopontin (OPN) staining were performed. Quantitative analysis of mineralized new bone to total volume (BV/TV) was assessed by micro-computed tomography. Results Both allografts demonstrated osteoinductive potential at 2 weeks as assessed by intramuscular bone formation. LifeNet DFDBA displayed continual new bone formation at 4 and 8 weeks, whereas Osteotech particles were fully resorbed by 4 weeks postimplantation. Femur defects demonstrated significantly greater BV/TV at 4 and 8 weeks with higher expression of OPN staining around LifeNet DFDBA particles. TRAP-positive cells were visible in and around both allograft materials. Conclusion The results from the present study indicate that variability among allografts exists. In the present, LifeNet DFDBA supported more new bone formation. Further larger animal models or clinical trials are required to validate these findings.

Introduction: Sufficient regeneration has been only reported in 2- or 3-wall periodontal defects and it appears to be difficult in cases with supra-alveolar periodontal defect. Aim: In this research, we will explore the periodontal regeneration of bone morphogenetic protein-2 (BMP-2) coprecipitated biomimetic calcium phosphate (BioCaP) (BMP-2-cop.BioCaP) in an experimental periodontitis model with supra-alveolar periodontal defect.Methods: Chronic experimental periodontitis model with supra-alveolar periodontal defect was created in the mandibular of beagle dogs. The defects were randomly assigned with BMP-2-cop.BioCaP + Bio-Gideu00ae, BioCaP + Bio-Gideu00ae, Bio-Ossu00ae + Bio-Gideu00ae, Bio-Gideu00ae or no grafts (N=6). After 8 weeks, clinical parameters, microcomputed tomography (micro-CT) examinations and histomorphmetric analysis were evaluated to access periodontal regeneration. Results: Clinical appearances including plaque index, bleeding index and probing depth were similar for all experimental conditions. In contrast, the attachment loss was significantly reduced in defects receiving BMP-2-cop.BioCaP. Besides the result from Micro-CT show much more bone regeneration in BMP-2-cop.BioCaP filled defect than other groups. Conclusion: These results suggest that BMP-2-cop.BioCaP can be a benefit biomaterial for periodontal regeneration with supra-alveolar periodontal defects.

Osteoporosis is one of the most widely occurring bone disorders characterized by low bone mineral density and poor bone strength. Strontium ranelate, as a treatment option, has received significant attention in recent years due to its ability to halt the progress of osteoporosis by simultaneously improving bone formation and reducing bone resorption. Although much emphasis has been given to the treatment of osteoporosis and fracture prevention using pharmacological agents, much less attention has been placed on the repair of critical-sized bone fractures caused by osteoporosis. The aim of the present study was to prepare strontium-incorporated mesoporous bioactive glass (Sr-MBG) scaffolds in order to combine the therapeutic effects of Sr2+ ions on osteoporosis with the bioactivity of MBG to regenerate osteoporotic-related fractures. Prior to animal implantation, the effects of Sr-containing ionic products from Sr-MBG scaffolds on the proliferation and differentiation of bone marrow stromal cells (BMSCs) from osteoporotic bone were investigated in an in vitro culture system. The results showed that Sr-MBG scaffolds significantly increased the proliferation of BMSCs in a concentration dependent manner and were able to stimulate the expression of osteoblast differentiation markers including Alpl, Col1a1, Runx2 and Bglap as assessed by real-time PCR. Critical sized femur defects in ovariectomised rats were created to simulate an osteoporotic phenotype. At time points 2, 4 and 8 weeks post-implantation, the in vivo osteogenetic efficiency was systematically evaluated by μCT analysis, hematoxylin and eosin staining, and immunohistochemistry (type I collagen). The results showed that the incorporation of Sr into MBG scaffolds significantly stimulated new bone formation in osteoporotic bone defects when compared to MBG scaffolds alone. Furthermore, it was generally found that Sr release in blood was maintained at a very low level and the Sr, Si, Ca and P excretion by urine operated in an a similar manner to blank control animals. Our results suggested that Sr-MBG scaffolds could be a promising biomaterial for regenerating osteoporosis-related fractures by the release of Sr-containing ionic products.

The delivery of novel bioactive scaffolds for the repair of bone defects remains a prominent challenge worldwide. Currently osteoporosis, a disease caused by low bone mineral density affects over 200 million people worldwide with up to half of this population experiencing at least one fracture within their lifetime. Recently temperature-sensitive p(N-isopropylacrylamide-co-butyl methylacrylate) nanogel (PIB nanogel) scaffolds have emerged as biomaterial candidate for regenerative therapies. It has the advantage of being injected from syringes as a soluble gel form (capable of delivering growth and/or living progenitor cells) yet hardens once it reaches body temperatures. Although this material demonstrates optimal clinical delivery of scaffolds, its main drawback is its low osteoconductivity and bioactivity. Recently we have demonstrated that mesoporous bioactive glass (MBG) loaded with strontium was able to regenerate osteoporotic defects in vivo and enhance osteoblast differentiation in vitro. The aim of this study was to combine the advantages of these two therapies and prepare PIB-nanogel scaffolds containing Sr-MBG and investigate their ability to regenerate femur defects created in ovarectamized rats. The results demonstrate that groups containing Sr-MBG within the nanogel formulation had significantly higher new bone formation when compared with other modalities. We further demonstrate that although nanogel demonstrated poor osteogenic ability, the addition of osteoblasts worked synergistically with Sr-MBG particles to enhance the regeneration of the created femur defects in osteoporotic animals. In conclusion, PIB nanogel scaffolds are a viable treatment modality for bone tissue engineering and may serve as a carrier-scaffold for osteogenic cells and/or bioactive scaffolds such as Sr-MBG. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1175-1183, 2017.