Comparison of Stabilizer Effects on the Size, Dispersion, and Catalytic Property of Pt, PtCu, and PtRu Nanoparticles.

Carbon-supported Pt, Pt-Cu, and Pt-Ru nanoparticles were prepared by an alcohol reduction method in the presence of carboxylates and phosphinate in order to investigate the role of these stabilizers in the nanoparticle formation process and the effect on catalytic properties in 2-propanol oxidation. For the Pt-Cu system, long chain carboxylate gave small dispersed particles even with high metal loading while phosphinate gave aggregated particles. For the Pt and Pt-Ru systems, fewer aggregates were observed and the particle size was independent of the chain length of carboxylate while much smaller and dispersed particles were obtained with phosphinate.

Comparison of Quantitative Antifungal Testing Methods for Textile Fabrics.

　Quantitative antifungal testing methods for textile fabrics under growth-supportive conditions were studied. Fungal growth activities on unfinished textile fabrics and textile fabrics modified with Ag nanoparticles were investigated using the colony counting method and the luminescence method. Morphological changes of the fungi during incubation were investigated by microscopic observation.

X-ray-induced reduction of Au ions in an aqueous solution in the presence of support materials and in situ time-resolved XANES measurements.

Synchrotron X-ray-induced reduction of Au ions in an aqueous solution with or without support materials is reported. To clarify the process of radiation-induced reduction of metal ions in aqueous solutions in the presence of carbon particles as support materials, in situ time-resolved XANES measurements of Au ions were performed under synchrotron X-ray irradiation. XANES spectra were obtained only when hydrophobic carbon particles were added to the precursor solution containing Au ions.

New protein purification system using gold-magnetic beads and a novel peptide tag, "the methionine tag".

Gold magnetic particles (GMP) are magnetic iron oxide particles modified with gold nanoparticles. The gold particles of GMP specifically bind to cysteine and methionine through Au-S binding. The aim of the present study was to establish a quick and easy protein purification system using novel peptide tags and GMP.

Simple PEG conjugation of SPIO via an Au-S bond improves its tumor targeting potency as a novel MR tumor imaging agent.

Gold/iron oxide magnetic nanoparticles are hybrid nanoparticles containing a core of magnetic iron oxide and surface colloidal gold, which allows for various biomaterials to be immobilized on the surface of the iron oxide nanoparticles via colloidal gold. Here, we developed a novel magnetic resonance (MR) imaging agent to broaden the MR tumor-imaging spectrum of superparamagnetic iron oxide nanoparticles (SPIO), e.g.

Direct cell entry of gold/iron-oxide magnetic nanoparticles in adenovirus mediated gene delivery.

Gold/iron-oxide MAgnetic Nanoparticles (GoldMAN) imparts useful magnetic properties to various biomolecules. Gold nanoparticles immobilized on the surface of magnetic nanoparticles allow for the conjugation of biomolecules via an Au-S bond. Here, we present a practical application by utilizing GoldMAN and a magnetic field to induce intracellular transduction.

Sonochemical immobilization of noble metal nanoparticles on the surface of maghemite: mechanism and morphological control of the products.

Aqueous sample solutions containing noble metal ions (HAuCl4, Na2PdCl4, H2PtCl6), polyethyleneglycol monostearate, and magnetic maghemite nanoparticles were irradiated with high power ultrasound. Analyses of the products showed that noble metal ions were reduced by the effects of ultrasound, and the formed noble metal nanoparticles were uniformly immobilized on the surface of the maghemite. The present "one pot process" significantly simplifies the immobilization of noble metal nanoparticles on the surface of supports, compared with the conventional impregnation method.

Structural analysis of sonochemically prepared Au/Pd nanoparticles dispersed in porous silica matrix.

Bimetallic Au/Pd nanoparticles supported on a silica matrix were prepared by an ultrasonic technique. The samples heat-treated at 100, 200, 300 and 400 degrees C were examined with techniques of XRD (X-ray diffraction), TEM and XAS (X-ray absorption spectrometry) for studying correlation between their structure and the catalytic activity of hydrogenation of cyclohexene. Even after the heat treatment at 400 degrees C, the particles were smaller than 20 nm and well dispersed in the matrix without agglomeration nor sintering.

Sonochemical preparation of composite nanoparticles of Au/gamma-Fe2O3 and magnetic separation of glutathione.

We prepared Au/gamma-Fe2O3 composite nanoparticles by sonochemically reducing Au(III) ions employing no stabilizer in the aqueous solution to form stable Au nanoparticles and allowing them to attach onto the surface of gamma-Fe2O3 particles with an average size of 21 nm. Size of the formed Au nanoparticle depended on the initial concentration of Au(III) ions. The number of the Au nanoparticles, supported on each gamma-Fe2O3 particle was controlled by changing the relative amounts of Au(III) ions and gamma-Fe2O3 particles.

Radiolysis of aqueous phenol solutions with nanoparticles. 1. Phenol degradation and TOC removal in solutions containing TiO2 induced by UV, gamma-ray and electron beams.

Aqueous phenol solutions containing TiO(2) nanoparticles were irradiated with ultraviolet (UV), gamma-ray and electron beams. Organic compounds were fully removed by each type of radiation in the presence of the particles. The absorbed energy of the ionizing radiation (gamma-ray and electron beams) needed for removal was much lower than that of UV photocatalysis.