title: Fabrication of silica-coated gold nanorods and investigation of their property of photothermal conversion.
abstract: This study described the preparation of silica-coated Au nanorods (AuNR/SiO2) in a colloidal solution, assessed their property of photothermal conversion, and investigated their ability to kill cancer cells using photothermal conversion. Au-seed nanoparticles were produced by reducing hydrogen tetrachloroaurate (HAuCl4) with sodium borohydride (NaBH4) in aqueous n-hexadecyltrimethylammonium bromide (CTAB) solution. AuNRs were then fabricated by reducing HAuCl4and silver nitrate (AgNO3) with l-ascorbic acid in the aqueous CTAB solution in the presence of Au-seed nanoparticles. The as-prepared AuNRs were washed by a process composed mainly of centrifugation to remove the CTAB. The washed AuNRs were coated with silica by mixing the AuNR colloidal solution, an aqueous solution of (3-aminopropyl)trimethoxysilane, and tetraethylorthosilicate/ethanol solution with a water/ethanol solution. We found that the addition of AuNR/SiO2in water, in mice, and in a culture medium with cancer cells, followed by irradiation with a laser, cause an increase in temperature, demonstrating that AuNR/SiO2have the ability of photothermal conversion. In addition, the cancer cells in the culture medium were found to be killed due to the increase in temperature caused by the photothermal conversion.
authors.affiliation: Department of Biomolecular Functional Engineering, College of Engineering, Ibaraki University, 4-12-1 Naka-narusawa-cho, Hitachi, Ibaraki 316-8511, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Inose
authors.affiliation: Department of Nano-Medical Science, Graduate School of Medicine, Tohoku University, Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan; Department of Gastroenterological Surgery, Graduate School of Medicine, Tohoku University, Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Oikawa
authors.affiliation: Department of Biomolecular Functional Engineering, College of Engineering, Ibaraki University, 4-12-1 Naka-narusawa-cho, Hitachi, Ibaraki 316-8511, Japan.
authors.forename: Kyosuke
authors.initials: K
authors.lastname: Shibuya
authors.affiliation: Department of Medical Physics, Graduate School of Medicine, Tohoku University, Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Tokunaga
authors.affiliation: Department of Nano-Medical Science, Graduate School of Medicine, Tohoku University, Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan; Department of Gastroenterological Surgery, Graduate School of Medicine, Tohoku University, Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan.
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Hatoyama
authors.affiliation: Department of Biomolecular Functional Engineering, College of Engineering, Ibaraki University, 4-12-1 Naka-narusawa-cho, Hitachi, Ibaraki 316-8511, Japan.
authors.forename: Kouichi
authors.initials: K
authors.lastname: Nakashima
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medicine, Tohoku University, Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kamei
authors.affiliation: Department of Nano-Medical Science, Graduate School of Medicine, Tohoku University, Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan; Department of Medical Physics, Graduate School of Medicine, Tohoku University, Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan. Electronic address: gonda@med.tohoku.ac.jp.
authors.forename: Kohsuke
authors.initials: K
authors.lastname: Gonda
authors.affiliation: Department of Biomolecular Functional Engineering, College of Engineering, Ibaraki University, 4-12-1 Naka-narusawa-cho, Hitachi, Ibaraki 316-8511, Japan. Electronic address: yoshio.kobayashi.yk@vc.ibaraki.ac.jp.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Kobayashi
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D051379:Mice; D046529:Microscopy, Electron, Transmission; D043942:Nanotubes / Q000737:chemistry*; D013696:Temperature
chemical_list: D002593:Cetrimonium Compounds; D006046:Gold; D000077286:Cetrimonium
keywords: Au; Core-shell; Nanorod; Photothermal conversion; Silica; Sol-gel