TiO2 microspheres containing magnetic nanoparticles for intra-arterial hyperthermia

Magnetic microspheres measuring 15–35 µm in diameter are believed to be useful for intra-arterial hyperthermia. In this study, we attempted to prepare titanium dioxide (TiO2) microspheres containing magnetic nanoparticles (MNPs). MNP-containing TiO2 microspheres with diameters of approximately 30 µm were successfully obtained by sol–gel reaction of titanium tetraisopropoxide in a water-in-oil emulsion with added cosurfactant of 1-butanol and subsequent heat treatment at 200°C. The microspheres showed ferrimagnetism owing to high content of MNPs in approximately 60 wt % and had a low-crystalline TiO2 matrix. Furthermore, the agar phantom was heated to above 43°C after approximately 1 min under an alternating magnetic field of 100 kHz and 300 Oe and showed in vitro biocompatibility similar to that of MNP-free TiO2 microspheres. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2308–2314, 2017

燃焼の火力および危険性に関する評価

Various materials are burned in outdoor activities and natural disasters. The purpose of thisstudy was to observe the thermal power and dangerous level of combustion. In experiment 1a,the highest thermal power was obtained when disposable chopsticks were burned using itto-kanstove of own making. In experiment 1b, the thermal power of bincho charcoal was superior. Inexperiment 2a, the temperature of ceiling of simulated shelter was measured. Two conditions,namely, three sidewalls and non-sidewall were prepared. The temperature of ceiling was147.1℃ in the former and 66.1℃ in the latter with the ceiling height of 40cm. In experiment2b, we observed the flammability of withered leaf. We discussed the suitability regarding newindexes of thermal power suggested by us and the properties of danger of fire

Visible-Light-Enhanced Antibacterial Activity of Silver and Copper Co-Doped Titania Formed on Titanium via Chemical and Thermal Treatments

Dental implants made of titanium (Ti) are used in dentistry, but peri-implantitis is a serious associated problem. Antibacterial and osteoconductive Ti dental implants may decrease the risk of peri-implantitis. In this study, titania (TiO2) co-doped with silver (Ag) at 2.5 at.% and copper (Cu) at 4.9 at.% was formed on Ti substrates via chemical and thermal treatments. The Ag and Cu co-doped TiO2 formed apatite in a simulated body fluid, which suggests osteoconductivity. It also showed antibacterial activity against Escherichia coli, which was enhanced by visible-light irradiation. This enhancement might be caused by the synergistic effect of the release of Ag and Cu and the generation of •OH from the sample. Dental implants with such a Ag and Cu co-doped TiO2 formed on their surface may reduce the risk of peri-implantitis