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Facile and direct synthesis of porous nanorod-type graphitic carbon nitride/CuO composite ( CuO- g-C3N4) has been achieved by using a Cu-melamine supramolecular framework as a precursor. The CuO- g-C3N4 nanocomposite demonstrated improved visible-light-driven photocatalytic activities. The results indicate that metal-melamine supramolecular frameworks can be promising precursors for the preparation of efficient g -C3N4 nanocomposite photocatalysts. [ABSTRACT FROM AUTHOR]

ZIF-67@Yeast was synthesized with in-situ growth procedure by using hydrothermally carbonized yeast as the substrate material. The prepared ZIF-67@Yeast was characterized in detail by SEM, BET, XRD and TG analysis. In addition, the adsorption properties of Pb2+ by ZIF-67@Yeast were also investigated. The results show that the adsorption capacity of Pb2+ by ZIF-67@Yeast is larger than the sum of the adsorption capacity of Pb2+ by individual yeast and ZIF-67. Yeast could maintain a stable morphology after hydrothermal carbonization at 180 °C. Therefore, many MOFs synthesized by hydrothermal or microwave methods at 180 °C could also be compounded with Yeast as a base material. This provides more possibilities that heavy metal ions are adsorbed by the synthesis of more diverse MOFs composites. ZIF-67@Yeast was synthesized by in situ growth using a hydrothermally carbonized yeast as a substrate material, which can maintain a stable morphology and efficient removal of Pb2+ in water. Image 1 • ZIF-67@Yeast was synthesized by using a hydrothermally carbonized yeast as a substrate material. • The adsorption capacity of Pb2+ by ZIF-67@Yeast is larger than that of Pb2+ by individual yeast and ZIF-67. • Many MOFs could also be compounded with yeast as a base material. [ABSTRACT FROM AUTHOR]

The organic-inorganic bioceramic composite microneedles (MNs) were prepared from hydroxyapatite (Hap) and gelatin (Gel) via a template method. The resultant hydroxyapatite and gelatin composite MNs exhibited low cytotoxicity and excellent mechanical properties. After transdermal administration to the diabetic rats, the insulin could be released from bioceramic composite MNs. An obvious and effective hypoglycemic effect could be obtained compared with that of subcutaneous injection route. This work suggests that bioceramic composite MNs containing of insulin have a potential application in diabetes treatment via transdermal ingestion. [ABSTRACT FROM AUTHOR]

A facile and green reversed-phase microemulsion co-precipitation method has been developed for fabrication of CaCO 3 -based composite nanocarriers (NCs) with hyaluronic acid (HA) coatings for oral delivery of insulin. The cell viability of resultant CaCO 3 -based composite NCs against HT-29 cells was analyzed with different concentration. The chemical stability of loaded insulin against digestive enzyme was established in presence of simulated gastric fluid (SGF) containing pepsin. The uptake behavior of HT-29 cells was evaluated by confocal laser scanning microscope (CLSM). After oral administration to the diabetic rats, an effective hypoglycemic effect was obtained compared with subcutaneous injection of insulin. [ABSTRACT FROM AUTHOR]

Development of an oral delivery strategy for insulin therapeutics has drawn much attention in recent years. In this study, a glucose-responsive nanocarriers for loading of insulin has been prepared firstly. The resultant nanocarriers exhibited relative low cytotoxicity against Caco-2 cells and excellent stability against protein solution. The insulin release behaviors were evaluated triggered by pH and glucose in vitro . In order to enhance the oral bioavailability of insulin, the insulin-loaded glucose-responsive nanocarriers were further encapsulated into a three-dimensional (3D) hyaluronic acid (HA) hydrogel environment for overcoming multiple barriers and providing multi-protection for insulin during the transport process. The hypoglycemic effect for oral delivery of insulin was studied in vivo . After oral administration to the diabetic rats, the released insulin from hydrogel systems containing insulin-loaded glucose-responsive nanocarriers exhibited an effective hypoglycemic effect for longer time compared with insulin-loaded nanocarriers. [ABSTRACT FROM AUTHOR]

In this paper, a hollow sulfur@graphene oxide core–shell composite is synthesized for high-performance lithium-sulfur batteries through a facile two-step solution method with the assistance of polyvinylpyrrolidone. Scanning electron microscope observation shows that the hollow sulfur sphere is coated by the homogeneous graphene oxide nanolayer, and thermogravimetric analysis demonstrates the composite holds sulfur loading as high as 92 wt%. The composite served as cathode in lithium-sulfur batteries shows its capacity as high as 745 mAh g −1 at 0.2C after 20 cycles. It also has an excellent cycling stability even at a high current density of 1C (73% retention and 96% coulombic efficiency after 150 cycles), implying that the diffusion of the polysulfides into electrolyte can be greatly inhibited. It is believed that the structure design of graphene oxide coated hollow sulfur sphere can be developed for the practical application of high-performance lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]

Abstract: Deep infection of prosthesis is one of the most frequent complications after joint replacement. One of the most effective ways is to introduce directly some antibiotics in the local site of the surgery. In the present study, an antimicrobial composite has been fabricated using nano-hydroxyapatite particles as carriers for the antimicrobial drug of vancomycin hydrochloride (VAN) and the mixture of oxidation sodium alginate (OSA) and gelatin (GT) as a sticky matrix. Samples have been characterized using X-ray diffraction instrument (XRD), field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM) and Fourier transform infrared (FTIR) spectra, Brunauer–Emmett–Teller (BET) methods, the rotational rheometer and the texture analyzer. The release of VAN from nano-hydroxyapatite (nHAP) particles was detected by the ultraviolet–visible (UV–vis) spectrophotometer and then bactericidal property of the composite was evaluated using the Staphylococcus aureus (S. aureus) as a bacterial model. Experimental results showed that the composite possessed an adhesive property derived from the gel of OSA and GT, which implied that the composite could bond directly to the fracture surface of bones in surgery. Furthermore, VAN was loaded efficiently on the surface of nHAP particles and could be released slowly from these particles, which endowed the composite with an obvious and continuous antimicrobial performance. The sticky and antimicrobial composite may has a potential application in arthroplasty to overcome deep infection in a simple and direct manner. [Copyright &y& Elsevier]

Abstract: Cuprous oxide (Cu2O) nanocrystals have been successfully synthesized using copper acetate as precursors via a polyol process. The as-synthesized products were easily deposited on the surface of carbon nanofibres (CNFs) and then were characterized through XRD, FESEM, TEM and FTIR, etc. The photocatalytic performance of these composite films was evaluated using methyl orange as a model organic compound under visible light irradiation. Results showed that the shape of Cu2O nanparticles could be changed from irregular nanoparticle to cubic, flower-like particle assembled by Cu2O nanocubes with the change of the reaction conditions. All of these Cu2O/CNFs composite films showed the satisfied photocatalytic activity to methyl orange even after 3 cycles of degradation experiment due to the protectable function of carbon fibre films to the Cu2O nanocrystals. The Cu2O/CNFs composite films may offer a feasible method for the potential application of Cu2O nanocrystals in the treatment of organic contamination. [Copyright &y& Elsevier]

Abstract: In order to develop an eco-friendly superabsorbent composite, flax yarn waste (FYW) was used as raw material to synthesize a novel flax yarn waste-g-poly(acrylic acid-co-acrylamide) (FYW/PAA) superabsorbent composite. Acrylic acid (AA) and acrylamide (AM) were grafted onto the pretreated flax yarn waste (PFYW) by free-radical graft copolymerization in homogeneous aqueous solution. The properties and synthesis conditions of the FYW/PAA superabsorbent composite were investigated. As a result, the prepared FYW/PAA attained the best water absorbency of 875g/g in distilled water, 490g/g in rainwater and 90g/g in 0.9wt% NaCl solution. The urea loading percentage of FYW/PAA could be modulated by the concentration of urea. The release of urea from FYW/PAA in water showed a typical three-stages sustained release behavior. Meanwhile, a weight residue of 53.6wt% was attained after being buried in soil for 90d. [Copyright &y& Elsevier]

Abstract: Novel composite films of Bombyx mori silk fibroin (SF) and hydroxyapatite (HA) composite films, with glycerin as an additive, were fabricated by means of co-precipitation, where the theoretical HA content was varied from 2 (w/w)% to 31 (w/w)%. The structure and properties of the composite films were investigated by SEM, XRD, AFM, TGA and tensile testing. The results showed that the composite films were smooth and transparent with the uniform distribution of HA into the composites when the final HA content was lower than 21 (w/w)%. XRD and TGA data showed that the silk fibroin in the composites was predominantly in a β-sheet crystalline structure, which was induced not only by the addition of glycerin, also by the HA crystal growth during the composite fabrication, leading to the thermal stable composite films. On the other hand, the HA crystals had the anisotropic growth with high extent of lattice imperfection and the preferential orientation along c-axis, probably promoted by the silk fibroin. The mechanical testing results showed that both break strain and stress were declined with the increase of HA content in the composites, presumably due to the original brittleness of HA compound. [Copyright &y& Elsevier]