title: Synthesis of magnetic alloy-filling carbon nanoparticles in super-critical benzene irradiated with an ultraviolet laser.
abstract: Magnetic nanoparticles are of great importance particularly in the field of biomedicine as well as nanotechnology and nano materials science and technology. Here, we synthesise magnetic alloy-filling carbon nanoparticles (MA@C NPs) via the following two-step procedure; (1) Irradiation of a laser beam of 266 nm wavelength into super-critical benzene, in which both ferrocene and cobaltocene are dissolved, at 290 °C; and (2) annealing of the particles at 600 and 800 °C. We find that the core particles are composed of cobalt (Co), iron (Fe) and oxygen (O) and covered with carbon layers. The structure of the core particles as-synthesised, and annealed at 600 and 800 °C, is, respectively, amorphous, CoFe2O4and FeCo. We also investigate the viability of L929 cells in the presence of MA@C NPs and find that there is no serious advert effect of the MA@C NPs on the cell viability thanks to the carbon layers covering the core particles. The magnetic properties are well characterised. The saturation and remnant magnetisation and coercivity increase and as a result, the hyperthermic efficiency becomes higher with an increase in the annealing temperature. The further modification of the surface of the present particles with several functional molecules becomes easier due to the carbon layers, which makes the present particles more valuable. It is therefore supposed that the presently synthesised MA@C NPs may well be utilised for nanotechnology-based biomedical engineering; e.g., nano bioimaging, nano hyperthermia and nano surgery.
authors.affiliation: Graduate School of Interdisciplinary New Science, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Hayasaki
authors.affiliation: Bio-Nano Electronics Research Centre, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Hasumura
authors.affiliation: Bio-Nano Electronics Research Centre, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Fukuda
authors.affiliation: Bio-Nano Electronics Research Centre, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Nagaoka
authors.affiliation: Bio-Nano Electronics Research Centre, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan.
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Ukai
authors.affiliation: Graduate School of Interdisciplinary New Science, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan.
authors.forename: Seiki
authors.initials: S
authors.lastname: Iwai
authors.affiliation: Graduate School of Interdisciplinary New Science, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan; Bio-Nano Electronics Research Centre, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Uchida
authors.affiliation: Graduate School of Interdisciplinary New Science, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan; Bio-Nano Electronics Research Centre, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Maekawa
keywords: Engineering; Inorganic chemistry; Materials science; Physical chemistry