title: Au nanorod design as light-absorber in the first and second biological near-infrared windows for in vivo photothermal therapy.
abstract: Photothermal cancer therapy using near-infrared (NIR) laser radiation is an emerging treatment. In the NIR region, two biological transparency windows are located in 650-950 nm (first NIR window) and 1000-1350 nm (second NIR window) with optimal tissue transmission obtained from low scattering and energy absorption, thus providing maximum radiation penetration through tissue and minimizing autofluorescence. To date, intensive effort has resulted in the generation of various methods that can be used to shift the absorbance of nanomaterials to the 650-950 nm NIR regions for studying photoinduced therapy. However, NIR light absorbers smaller than 100 nm in the second NIR region have been scant. We report that a Au nanorod (NR) can be designed with a rod-in-shell (rattle-like) structure smaller than 100 nm that is tailored to be responsive to the first and second NIR windows, in which we can perform hyperthermia-based therapy. In vitro performance clearly displays high efficacy in the NIR photothermal destruction of cancer cells, showing large cell-damaged area beyond the laser-irradiated area. This marked phenomenon has made the rod-in-shell structure a promising hyperthermia agent for the in vivo photothermal ablation of solid tumors when activated using a continuous-wave 808 m (first NIR window) or a 1064 nm (second NIR window) diode laser. We tailored the UV-vis-NIR spectrum of the rod-in-shell structure by changing the gap distance between the Au NR core and the AuAg nanoshell, to evaluate the therapeutic effect of using a 1064 nm diode laser. Regarding the first NIR window with the use of an 808 nm diode laser, rod-in-shell particles exhibit a more effective anticancer efficacy in the laser ablation of solid tumors compared to Au NRs.
authors: Department of Chemistry, Center for Micro/Nano Science and Technology, and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan, 701 Taiwan.
authors: Ming-Fong
authors: MF
authors: Tsai
authors: Shih-Hui Gilbert
authors: SH
authors: Chang
authors: Fong-Yu
authors: FY
authors: Cheng
authors: Vijayakumar
authors: V
authors: Shanmugam
authors: Yu-Sheng
authors: YS
authors: Cheng
authors: Chia-Hao
authors: CH
authors: Su
authors: Chen-Sheng
authors: CS
authors: Yeh
mesh_terms: D000042:Absorption; D000818:Animals; D045744:Cell Line, Tumor; D006046:Gold / Q000737:chemistry*; D007259:Infrared Rays; D007834:Lasers; D008175:Lung Neoplasms / Q000532:radiotherapy; D008297:Male; D051379:Mice; D043942:Nanotubes / Q000737:chemistry* / Q000633:toxicity; D011092:Polyethylene Glycols / Q000737:chemistry; D011878:Radiotherapy / Q000379:methods*; D012834:Silver / Q000737:chemistry
chemical_list: D012834:Silver; D011092:Polyethylene Glycols; D006046:Gold