title: Carbon-Coated Gold Nanorods: A Facile Route to Biocompatible Materials for Photothermal Applications.
abstract: Gold nanorods and their core-shell nanocomposites have been widely studied because of their well-defined anisotropy and unique optical properties and applications. This study demonstrates a facile hydrothermal synthesis strategy for generating carbon coating on gold nanorods (AuNRs@C) under mild conditions (<200 °C), where the carbon shell is composed of polymerized sugar molecules (glucose). The structure and composition of the produced core-shell nanocomposites were characterized using advanced microscopic and spectroscopic techniques. The functional properties, particularly the photothermal and biocompatibility properties of the produced AuNRs@C, were quantified to assess their potential in photothermal hyperthermia. These AuNRs@C were tested in vitro (under representative treatment conditions) using near-infrared (NIR) light irradiation. It was found that the AuNRs produced here exhibit exemplary heat generation capability. Temperature changes of 10.5, 9, and 8 °C for AuNRs@C were observed with carbon shell thicknesses of 10, 17, and 25 nm, respectively, at a concentration of 50 μM, after 600 s of irradiation with a laser power of 0.17 W/cm(2). In addition, the synthesized AuNRs@C also exhibit good biocompatibility toward two soft tissue sarcoma cell lines (HT1080, a fibrosarcoma; and GCT, a fibrous histiocytoma). The cell viability study shows that AuNRs@C (at a concentration of <0.1 mg/mL) core-shell particles induce significantly lower cytotoxicity on both HT1080 and GCT cell lines, as compared with cetyltrimethylammonium bromide (CTAB)-capped AuNRs. Furthermore, similar to PEG-modified AuNRs, they are also safe to both HT1080 and GCT cell lines. This biocompatibility results from a surface full of -OH or -COH groups, which are suitable for linking and are nontoxic Therefore, the AuNRs@C represent a viable alternative to PEG-coated AuNRs for facile synthesis and improved photothermal conversion. Overall, these findings open up a new class of carbon-coated nanostructures that are biocompatible and could potentially be employed in a wide range of biomedical applications.
authors.affiliation: School of Materials Science and Engineering, The University of New South Wales , Sydney, New South Wales 2052, Australia.
authors.forename: Yusuf Valentino
authors.initials: YV
authors.lastname: Kaneti
authors.affiliation: School of Materials Science and Engineering, The University of New South Wales , Sydney, New South Wales 2052, Australia.
authors.forename: Chuyang
authors.initials: C
authors.lastname: Chen
authors.affiliation: Department of Chemical Engineering, Monash University , Clayton, Victoria 3800, Australia.
authors.forename: Minsu
authors.initials: M
authors.lastname: Liu
authors.affiliation: Sarcoma and Nanooncology Group, Adult Cancer Program, prince of Wales Clinical School and Lowy Cancer Research Centre, Faculty of Medicine, The University of New South Wales , Sydney, New South Wales 2052, Australia.
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Wang
authors.affiliation: Sarcoma and Nanooncology Group, Adult Cancer Program, prince of Wales Clinical School and Lowy Cancer Research Centre, Faculty of Medicine, The University of New South Wales , Sydney, New South Wales 2052, Australia.
authors.forename: Jia Lin
authors.initials: JL
authors.lastname: Yang
authors.affiliation: School of Mechanical and Manufacturing Engineering, The University of New South Wales , Sydney, New South Wales 2052, Australia.|School of Photovoltaic and Renewable Energy Engineering, The University of New South Wales , Sydney, New South Wales 2052, Australia.
authors.forename: Robert Allen
authors.initials: RA
authors.lastname: Taylor
authors.affiliation: Department of Chemical Engineering, Monash University , Clayton, Victoria 3800, Australia.
authors.forename: Xuchuan
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Department of Chemical Engineering, Monash University , Clayton, Victoria 3800, Australia.
authors.forename: Aibing
authors.initials: A
authors.lastname: Yu
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis*; D002244:Carbon / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D006979:Hyperthermia, Induced; D008422:Materials Testing; D036103:Nanotechnology / Q000379:methods*; D043942:Nanotubes / Q000737:chemistry / Q000648:ultrastructure; D010789:Phototherapy; D013056:Spectrophotometry, Ultraviolet
chemical_list: D001672:Biocompatible Materials; D002244:Carbon; D006046:Gold
keywords: carbon-coated gold nanorods; core−shell nanocomposites; cytotoxicity; gold nanorods; photothermal treatment