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Removal of copper ion (Cu2+) using water-soluble porphyrin and dextran was investigated. Cu2+ can be removed using dextran very rapidly in the form of a [(TMPyP) Cu]4+ complex, and the extent of removal can reach almost 100% with the addition of acetone. Electron paramagnetic resonance (EPR) results confirm the existence of Cu2+ in precipitates. The order in which dextran and acetone are added strongly influences the removal of Cu2+. This work suggests an efficient method to remove Cu2+ ions from waste water. [ABSTRACT FROM AUTHOR]

Luminescent europium(III)-doped nanoporous silica nanospheres (Eu:NPS) were successfully synthesized, and a folate N-hydroxysuccinimidyl ester (FA-NHS) molecule as a targeting ligand for cancer cells was immobilized on the nanosphere surfaces through mediation of the 3-aminopropyltriethoxysilane (APTES) adlayer. The ordered nanopores were preserved by the immobilization, and the specific surface area decreased only with the APTES immobilization, suggesting that the FA-NHS was predominantly immobilized on the outer surface of the nanopores. The photoluminescence of the nanospheres functionalized with folic acid (FA) exhibited a characteristic peak due to the interactions (e.g., energy transfer) between FA and Eu3+, and further the orange luminescence could be clearly detected by fluorescence microscopy in air and water. Furthermore, the nanospheres highly dispersed in cell culture medium exhibited nontoxicity in the cellular proliferation stages of the Hela cancer cells and NIH3T3 fibroblasts and specifically bind to the Hela cells. The nanospheres after the binding and uptake also showed intense luminescence from Therefore outer/inner cell surfaces for the culture time of 4 days. Therefore, the luminescent FA-functionalized Eu:NPS nanospheres could be used for specific targeting and imaging abilities for cancer cells. [ABSTRACT FROM AUTHOR]

Composites between carbon fibers (CFs) and heterogeneous materials have been widely researched, and fabrication techniques have been developed. However, because the CF surfaces are hydrophobic, they poorly disperse into hydrophilic resins and do not form junctions with ceramics. For designing and developing high-strength composites, it is important to investigate and design the interfacial chemical bonds. Thus, recently, research focusses on surface modification and coating techniques of CFs. In this review paper, various surface modification and coating by inorganic polymers (metal oxide compounds) were highlighted to focus the functionalization of the CF surfaces. The applications for novel composite materials was also investigated. Furthermore, the interfacial bonding techniques between CF and polymer resin for carbon fiber reinforced plastic and their future perspectives are reviewed and discussed. [ABSTRACT FROM AUTHOR]

A quartz crystal microbalance with dissipation (QCM-D) technique was employed to detecting the protein adsorption and subsequent osteoblast-like cell adhesion to hydroxyapatite (HAp) nanocrystals. The interfacial phenomena with the preadsorption of three proteins (albumin (BSA), fibronectin (Fn), and collagen (Col)), the subsequent adsorption of fetal bovine serum (FBS), and the adhesion of the cells were investigated. The QCM-D measured the frequency shift (Δf) and dissipation energy shift (ΔD), and the viscoelastic properties of the adlayers were evaluated using ΔD–Δfplot and Voigt-based viscoelastic model. The Col adsorption significantly showed higher Δf, ΔD, elasticity, and viscosity values as compared to the BSA and Fn adsorption, and the subsequent FBS adsorption depended on the preadsorbed proteins. The ΔD–Δfplot of the cell adhesion also showed a different behavior depending on the surfaces, and the Fn- and Col-modified surfaces showed the rapid mass and ΔDchanges by forming the viscous interfacial layers with cell adhesion, indicating that the processes were affected by the cellular reaction through the extracellular matrix (ECM) proteins. The confocal laser scanning microscope images of adherent cells showed a different morphology and pseudopod on the surfaces. The cells adhered to the surfaces modified with the Fn and Col had significantly uniaxially expanded shapes and fibrous pseudopods, and those modified with the BSA had a round shape. Therefore, the different cell–protein interactions would cause the arrangement of the ECM and the cytoskeleton changes at the interfaces, and these phenomena were successfully detected by the QCM-D and Voigt-based model. [ABSTRACT FROM AUTHOR]

The photoassisted fusion of a decanethiol-passivated Au-nanoparticle film on a glass substrate by exposure to vacuum-ultraviolet (vacuum-UV) light at 172 nm was investigated and compared to that by thermal fusion. On the basis of the thermal treatment at 200 °C, the X-ray diffraction patterns indicated that the Au-nanoparticle film with the particle diameter of 2.1 nm is completely converted to a crystalline Au film, and the film surface was coarsely granular, having a roughness of several tens of nanometers by field emission-scanning electron microscopy observation. After exposure to vacuum-UV light, the UV−vis absorption spectra revealed that the surface plasmon band at 535 nm showed a red shift with the increasing exposure time, and then the absorption band at 770 nm was clearly observed at 30 min. The diameter of the fused Au nanoparticles was larger than 20 nm on the basis of a transmission electron microscopy observation. These changes indicated that the Au nanoparticles were converted to the crystalline state due to photodecomposition of the decanethiol. Thus, the controllable mild fusion among neighboring Au nanoparticles at room temperature was achieved by vacuum-UV-light exposure due to photodecomposition of the decanethiol. [ABSTRACT FROM AUTHOR]

The states of tris(8-quinolinato)aluminum(iii) (Alq3) adsorbed in mesoporous silicas with different pore sizes (2.5, 3.1 and 5.0 nm) were investigated. Alq3was successfully occluded into the mesoporous silicas from solution and the adsorbed amount of Alq3per BET surface area was effectively controlled by changing the added amount Alq3to the solution. The state of Alq3in the mesopore varied depending on the pore size as well as the adsorbed amount of Alq3as revealed by variation of the photoluminescence spectra. The luminescence of the adsorbed Alq3was found to be temperature-dependent, indicating the mobility of the adsorbed Alq3to temperature variations. The temperature-dependence also depended on the pore size. The guest–guest interactions between Alq3molecules as well as the host–guest interactions between Alq3and the mesopore were controlled by the pore size. [ABSTRACT FROM AUTHOR]

A supercapacitor composite electrode was effectively fabricated by using cyclic voltammetric deposition of poly(pyrrole-co-2-formylpyrrole)-multiwall carbon nanotube composite, P(Py-co-FPy)-MWCNT. The charge storage of the three-dimensional nanofibril of the P(Py-co-FPy)-coated MWCNT composite electrode was excellent and reached the specific capacitive value of up to 535 F g-1. [ABSTRACT FROM AUTHOR]

Terbium(III)-doped mesoporous silicas were synthesized, and the states of terbium ions in the silica frameworks were investigated. The mesopores were preserved upon doping at terbium ion molar concentrations relative to (Si+Tb) up to 15 mol %, indicating the interaction of terbium ions with Si–O bonds. Significant morphological changes of the particles were observed with increasing the doping concentration. The shapes of the photoluminescence spectra due to the transitions of 5D4 → 7F6 and 5D4 → 7F5 were indicative of the presence of terbium ions in the silica matrix, and the quantum efficiency (2.1–2.8%) and lifetime (1.6–1.9 ms) decreased with increasing the doping concentration up to 15 mol %. Therefore, the terbium ions are considered to be located inside the amorphous silica frameworks, where they electrostatically interact with the O atoms of silanol and siloxane groups. [ABSTRACT FROM AUTHOR]

Waste bagasse of Agave tequilana-Weber fibers treated with sodium hydroxide was used to elaborate hydrogel films. The bagasse was offered in an alternative use for the preparation of hydrogel films by phase inversion method without crosslinking and further purification of cellulose. The effect on the properties of the obtained films was studied when the chemical treatment of the agave fibers was changed. It was found that the resultant hydrogels showed increment in tensile from 40 N/mm² to 56 N/mm² with the increase of sodium hypochlorite concentration from 1 to 10 vol.%, respectively. With regard to biocompatibility properties of the hydrogel films, platelet adhesion, clotting time and protein adsorption were investigated. Analysis of the morphology of adherent NIH3T3 fibroblast indicated that the projected cell area, aspect ratio and long axis gradually increased with the increment of sodium hypochlorite content in the agave treatment. It was presented that the chemical treatment affects cell adhesion and morphology and lignin content remains in the brown fibers. [ABSTRACT FROM AUTHOR]

This paper reviews the recent progress in the preparation of oxide-based and heteroatom-doped particles. Surfactant-templated oxide particles, e.g. silica and titania, are possible candidates for various potential applications such as adsorbents, photocatalysts, and optoelectronic and biological materials. We highlight nanoporous oxides of one element, such as silicon or titanium, and those containing multiple elements, which exhibit properties that are not achieved with individual components. Although the multicomponent nanoporous oxides possess a number of attractive functions, the origin of their properties is hard to determine due to compositional/structural complexity. Particles with a well-defined size and shape are keys for a quantitative and detailed discussion on the unique complex properties of the particles. From this viewpoint, we review the synthesis techniques of the oxide particles, which are functionalized with organic molecules or doped with heteroatoms, the physicochemical properties of the particles and the possibilities for their photofunctional applications as complex systems.