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Abstract: Polyacrylonitrile (PAN)/silica composite fibers were fabricated by dry-jet wet spinning process. PAN/silica composite fibers were characterized with SEM and FTIR. The former revealed that beads were formed and aggregated when silica content was more than 1wt.%, while the latter confirmed the presence and increment of silica content. The tensile test was performed to obtain the mechanical properties of PAN/silica composite fibers, which showed an optimum Young''s modulus at 5.94GPa and tensile strength at 1.07MPa at 1wt.% silica. Therefore, the addition of silica particle at 1wt.% has enhanced the mechanical properties of PAN/silica composite fibers. [Copyright &y& Elsevier]

Abstract: Polyacrylonitrile (PAN)/acrylamide (AM) precursor fibers prepared using a solvent-free coagulation process were stabilized, carbonized, and physically activated by carbon dioxide (CO2) into activated carbon fibers (ACFs). The activation temperature varied from 800 to 900°C while the activation time was 60minutes. Scanning electron microscopy (SEM) micrographs show that the porosity increased after the activation process, resulting from the loss of volatile components. The specific surface area increased markedly after the activation process; it was several hundred times greater than before the process. It was concluded that there is a big potential for PAN/AM-based ACFs prepared using solvent-free coagulation bath as an adsorbent of natural gas. [Copyright &y& Elsevier]

• The nanofibrous diameter increased with increasing CEX concentration. • The nanofibrous possessed a great potential to take up water and tensile strength. • PCL/GelMA-CEX has a great inhibition against E. coli and S. aureus bacteria. • PCL/GelMA loading with low CEX concentration possessed great biocompatibility. • Wound healing process was enhanced with the PCL/GelMA-CEX nanofibrous. Infections, particularly those induced via drug resistant pathogens, can cause serious issues in wound healing process. In this study, cephalexin (CEX), as an effective antibiotic, was loaded into polycaprolactone (PCL)-gelatin methacryloyl (GelMA) nanofibrous by electrospinning for the development of a new wound dressing. The electrospun nanofibrous possessed continuous and smooth structure with the fiber diameters ranging from 280 to 330 nm. Swelling examination exhibited that the electrospun nanofibrous could take up water by 400–600%. Antibacterial activity of PCL/GelMA loading with CEX had a great inhibition towards both Gram-positive Staphylococcus aureus and negative-bacteria Escherichia coli. The hematoxylin-eosin (H&E) and Masson's trichrome (MT) staining results from treated wounds with PCL/GelMA-CEX nanofibrous exhibited improved re-epithelialization and collagen deposition. Taken together, our study illustrate the PCL/GelMA-CEX nanofibrous can be promising for use as an effective antibacterial wound dressing in skin regeneration. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Novel PMMA-Mon bone cement containing various amounts of carbon nanotubes is prepared. • PMMA-Mon/CNTs bone cement indicated high bioactivity and cytocompatibility. • Incorporation of CNTs into PMMA-Mon increases its tensile strength. • Cells adhesion and proliferation improved after addition of CNTs in PMMA-Mon. Abstract Treatment of bone defects requires materials or bone cement with superior mechanical properties and favorable biological properties, but this remains unachievable to date. To address this issue, the present study aimed to synthesize and characterize a novel poly(methyl methacrylate) (PMMA) bone cement containing monticellite (Mon) and carbon nanotubes (CNTs) for bone defect treatment. Considerably better mechanical properties were noted in the PMMA-Mon-CNT vs. PMMA and PMMA-Mon bone cements due to the unique resistance of CNTs to crack formation and propagation. Favorable bioactivity was also found in the bone cements containing Mon and CNTs, whereas the PMMA bone cement presented poor bioactivity. Specifically, the incorporation of Mon and CNTs into the PMMA matrix promoted the attachment of MG63 cells compared to the PMMA cement. Thus, the PMMA-Mon-CNT bone cements developed are good potential candidates for filling bone defects in orthopedic surgeries. [ABSTRACT FROM AUTHOR]

• The NC-PtNPs/RGO was fabricated by novel one-step chemical reduction-assisted hydrothermal method. • NC-PtNPs were successfully formed and deposited on the basal plane and edge of RGO. • The NC-PtNPs/RGO catalysts exhibit excellent catalytic activity and durability towards MOR. Nanocluster-like Pt nanoparticles/reduced graphene oxide nanocomposite catalyst (NC-PtNPs/RGO) was synthesized through a novel one-step process of chemical reduction-assisted hydrothermal reaction by using formic acid as reducing agent. The crystallinity, morphology and composition of the NC-PtNPs/RGO catalysts were extensively characterized. The as-prepared NC-PtNPs/RGO catalysts exhibited higher electro-catalytic activity towards methanol oxidation than carbon black (CB)/PtNPs catalyst and could be ascribed to the high dispersion of NC-Pt NPs with large electrochemical surface area, release more exposure of active sites by NC-PtNPs structure and synergy effect of RGO. [ABSTRACT FROM AUTHOR]

One of the most important therapeutic and economic concerns regarding surgery, is the occurrence of post-operative infections which leads to an increase in premature failure rate. Therefore, novel nanostructured baghdadite-vancomycin (Ba-Vac) scaffolds were prepared using the space holder method with good mechanical properties and controlled drug release to inhibit post-surgery infections. The results showed that the (Ba-Vac) scaffolds were attained with the pore size of 300–400 µm and total porosity of 80–82% with compressive strength of 0.86–0.88 MPa. In drug release profiles, a burst release was observed for 6 h, followed by a sustained release. Ba-Vac scaffolds presented good antibacterial activity toward Staphylococcus aureus ( S. aureus ). More attachment and spreading of MG-63 osteoblast cells on the Ba and Ba-(1-3 wt%)Vac scaffolds was also observed in comparison with the Ba-5 wt%Vac scaffold. Therefore, the Ba-(1–3 wt%)Vac scaffold is a good candidate for inhibiting post-surgery infections, as well as for bone tissue engineering. [ABSTRACT FROM AUTHOR]

In this study, gelatin-ciprofloxacin (Gel-Cip) nanofibers containing various amounts of Cip (0, 2, 4 and, 8 wt%) were fabricated on the surface of Mg-1Ca alloy via an electrospinning process. Microscopic characterization indicated a porous network structure with fiber diameters in the range of 150–170 nm. Prolonged drug release was attained from Gel-Cip nanofibers coating along with initial rapid drug release of around 20–22% during 12 h, followed by a slow release stage that can effectively control the infection. The incorporation of 2–4 wt% Cip into Gel nanofibers coating significantly increased the antibacterial performance and corrosion resistance of the uncoated Mg-Ca alloy without showing an inhibitory influence on the cytocompatibility characteristic. Hence, it is potentially appropriate as the novel electrospun nanofibers coating material for bone regeneration application. [ABSTRACT FROM AUTHOR]

The objective of this study is to produce superhydrophilic, low cost kaolin-based ceramic hollow fibre membrane (KHFM) for efficient oily-wastewater separation. The asymmetric KHFMs with short finger-like voids were successfully prepared via a combined phase inversion and sintering technique. It was observed that the increase in sintering temperature enhanced membrane mechanical strength and promoted significant changes on membrane morphology. The combination of hydrophilic characteristic (contact angle of 33°) and small pore size (0.35 μm) of the kaolin KHFM sintered at 1500 °C resulted in excellent oily wastewater separation, with a 100% success rate, thus indicating that KHFM is able to repel most of the oil and allow only water to pass through its pores. In conclusion, the developed KHFM can be regarded as a promising medium for oily wastewater separation. [ABSTRACT FROM AUTHOR]