title: Synthesis of Absorption-Dominant Small Gold Nanorods and Their Plasmonic Properties.
abstract: Absorption-dominant small Au nanorods with diameters of less than 10 nm are prepared using a facile seed-mediated growth method. The diameters of the small gold nanorods range from 6 to 9 nm, and their lengths vary from 16 to 45 nm. Their aspect ratios can be tailored from 2.7 to 4.7. As a result, the longitudinal plasmon resonance wavelengths are readily tunable from ∼720 nm to ∼830 nm by changing the seed-to-Au(III) molar ratio in the growth solution. The fractions of the scattering in the total extinction of the small Au nanorods are found to be in the range of 0.005 to 0.025 with finite-difference time-domain simulations, confirming that the extinction values of these small Au nanorods are dominantly contributed to by the light absorption. Moreover, the small Au nanorod sample is coated with a dense silica layer for photothermal therapy with three cell lines. It shows improved photothermal therapy performance compared to a large Au nanorod sample for the same cellular Au contents. Our study suggests that small Au nanorods are promising light absorbers and photothermal therapy agents.
authors.affiliation: †Department of Physics and ‡Department of Imaging and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
authors.forename: Henglei
authors.initials: H
authors.lastname: Jia
authors.affiliation: †Department of Physics and ‡Department of Imaging and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
authors.forename: Caihong
authors.initials: C
authors.lastname: Fang
authors.affiliation: †Department of Physics and ‡Department of Imaging and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Zhu
authors.affiliation: †Department of Physics and ‡Department of Imaging and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
authors.forename: Qifeng
authors.initials: Q
authors.lastname: Ruan
authors.affiliation: †Department of Physics and ‡Department of Imaging and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
authors.forename: Yi-Xiang J
authors.initials: YX
authors.lastname: Wang
authors.affiliation: †Department of Physics and ‡Department of Imaging and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
authors.forename: Jianfang
authors.initials: J
authors.lastname: Wang
mesh_terms: D065638:Absorption, Radiation; D001692:Biological Transport; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D006046:Gold / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D006801:Humans; D042541:Intracellular Space / Q000378:metabolism; D036103:Nanotechnology; D043942:Nanotubes / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry
chemical_list: D006046:Gold; D012822:Silicon Dioxide