scholarly journals Modeling the optical properties of a single gold nanorod for use in biomedical applications

2021 ◽  
Author(s):  
Yevgeniy Davletshin
Keyword(s):  
Optical Properties ◽  
Gold Nanorods ◽  
Biomedical Applications ◽  
Computational Models ◽  
Near Infrared ◽  
Gold Nanorod ◽  
Spatial Modulation ◽  
Element Analysis ◽  
Modulation Spectroscopy ◽  
Nir Light

Recent studies have shown that gold nanorods are highly effective agents for conversion of visible and near infrared (NIR) light into heat. Thermal therapy that utilizes this effect is called Plasmonic Photohermal Therapy (PPTT), where light absorption by photothermal agents (plasmon-resonant gold nanorods) caused kinetic energy to increase, resulting in heating of the area surrounding the agent. A primary understanding of optical and thermal properties of gold particles at nonscale level is still unclear. Due to the limitations of current equipment for nanoparticle characterization, numerical methods and computational models are widely used to understand the physic at the nanoscale. In this thesis fininte element analysis and spatial modulation spectroscopy were used to develop and test a computational model to characterize optical properties of a single gold nanorod.

scholarly journals Modeling the optical properties of a single gold nanorod for use in biomedical applications

2021 ◽  
Author(s):  
Yevgeniy Davletshin
Keyword(s):  
Optical Properties ◽  
Gold Nanorods ◽  
Biomedical Applications ◽  
Computational Models ◽  
Near Infrared ◽  
Gold Nanorod ◽  
Spatial Modulation ◽  
Element Analysis ◽  
Modulation Spectroscopy ◽  
Nir Light

Recent studies have shown that gold nanorods are highly effective agents for conversion of visible and near infrared (NIR) light into heat. Thermal therapy that utilizes this effect is called Plasmonic Photohermal Therapy (PPTT), where light absorption by photothermal agents (plasmon-resonant gold nanorods) caused kinetic energy to increase, resulting in heating of the area surrounding the agent. A primary understanding of optical and thermal properties of gold particles at nonscale level is still unclear. Due to the limitations of current equipment for nanoparticle characterization, numerical methods and computational models are widely used to understand the physic at the nanoscale. In this thesis fininte element analysis and spatial modulation spectroscopy were used to develop and test a computational model to characterize optical properties of a single gold nanorod.

scholarly journals Photothermal Therapy Using Gold Nanorods and Near-Infrared Light in a Murine Melanoma Model Increases Survival and Decreases Tumor Volume

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Mary K. Popp ◽  
Imane Oubou ◽  
Colin Shepherd ◽  
Zachary Nager ◽  
Courtney Anderson ◽  
...  
Keyword(s):  
Light Source ◽  
Gold Nanorods ◽  
Photothermal Therapy ◽  
Near Infrared ◽  
Tumor Volume ◽  
Infrared Light ◽  
Led Light ◽  
Murine Melanoma ◽  
Nir Light ◽  
Melanoma Model

Photothermal therapy (PTT) treatments have shown strong potential in treating tumors through their ability to target destructive heat preferentially to tumor regions. In this paper we demonstrate that PTT in a murine melanoma model using gold nanorods (GNRs) and near-infrared (NIR) light decreases tumor volume and increases animal survival to an extent that is comparable to the current generation of melanoma drugs. GNRs, in particular, have shown a strong ability to reach ablative temperatures quickly in tumors when exposed to NIR light. The current research tests the efficacy of GNRs PTT in a difficult and fast growing murine melanoma model using a NIR light-emitting diode (LED) light source. LED light sources in the NIR spectrum could provide a safer and more practical approach to photothermal therapy than lasers. We also show that the LED light source can effectively and quickly heatin vitroandin vivomodels to ablative temperatures when combined with GNRs. We anticipate that this approach could have significant implications for human cancer therapy.

scholarly journals Hyaluronate modified upconversion nanoparticles for near infrared light-triggered on–off tattoo systems

RSC Advances ◽  
2017 ◽  
Vol 7 (24) ◽  
pp. 14805-14808 ◽  
Author(s):  
Seulgi Han ◽  
Songeun Beack ◽  
Sanghwa Jeong ◽  
Byung Woo Hwang ◽  
Myeong Hwan Shin ◽  
...  
Keyword(s):  
Biomedical Applications ◽  
Near Infrared ◽  
Infrared Light ◽  
Upconversion Nanoparticles ◽  
Near Infrared Light ◽  
Nir Light

We successfully developed an NIR light-triggered in vivo on–off tattoo system using hyaluronate modified upconversion nanoparticles for various biomedical applications.

scholarly journals PREPARATION AND CHARACTERIZATION OF A NEAR-INFRARED LIGHT RESPONSIVE MICROCAPSULE SYSTEM FOR CANCER THERAPY

2014 ◽  
Vol 07 (01) ◽  
pp. 1350037 ◽  
Author(s):  
YINGFENG DI ◽  
SISI CUI ◽  
YUEQING GU
Keyword(s):  
Cancer Therapy ◽  
Gold Nanorods ◽  
Self Assembly ◽  
Near Infrared ◽  
Infrared Light ◽  
Layer By Layer ◽  
Near Infrared Light ◽  
Nir Light ◽  
Alternative Material ◽  
Confocal Fluorescence Imaging

A novel near-infrared light responsive microcapsule system, gold nanorod-covered DOX-loaded hollow CaCO 3 microcapsule ( AuNR -HM-DOX) is developed for cancer therapy. The hollow CaCO 3 microcapsules were prepared based on the self-assembly between chitosan and sodium alginate on CaCO 3 particles via layer-by-layer technique, and then covered with gold nanorods to obtain the microcapsule system. Upon near-infrared (NIR) irradiation, microcapsule with gold nanorods can convert the absorbed NIR light into heat. Meanwhile, doxorubicin (DOX), a chemotherapy drug, is loaded into the microcapsule system via electrostatic adsorption for combined photothermal therapy and chemotherapy. Properties of AuNR -HM-DOX including grain diameter, optical spectra were characterized. Confocal fluorescence imaging was performed to observe the morphology of the capsules and existence of DOX in the core, confirming the successful loading of DOX. The release of DOX from the capsules under continuous NIR irradiation was investigated to evaluate the temperature responsiveness of AuNR -HM-DOX. Results indicate that AuNR -HM-DOX microcapsules possess uniform particle size and high light responsiveness. The combination of chemical and physical therapy of AuNR -HM-DOX features great potential as an adjuvant therapeutic alternative material for combined cancer therapy.

scholarly journals Plasmon Enhanced Second Harmonic Generation from ZnO Nanofilms on Vertical Au Nanorod Arrays

Nanomaterials ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2597
Author(s):  
Qiang Ma ◽  
Chengda Pan ◽  
Yingxian Xue ◽  
Zhiyun Fang ◽  
Shiyu Zhang ◽  
...  
Keyword(s):  
Optical Properties ◽  
Second Harmonic Generation ◽  
Harmonic Generation ◽  
Gold Nanorods ◽  
Second Harmonic ◽  
Nanorod Array ◽  
Gold Nanorod ◽  
Nanorod Arrays ◽  
Plasmonic Enhancement ◽  
Vertically Aligned

Vertically aligned gold nanorod arrays have attracted much attention for their fascinating optical properties. Different from longitudinal surface plasmon wavelength (LSPW) and edge-to-edge spacing of gold nanorods, the role of gold nanorod diameter in plasmonic enhancement ability of vertical gold nanorod arrays has rarely been explored. In this work, we selected gold nanorods with similar LSPW but two different diameters (22 and 41 nm), the optical properties of which are dominated by absorption and scattering cross sections, respectively. The vertically aligned arrays of these gold nanorods formed by evaporation self-assembly are coupled with nonlinear ZnO nanocrystal films spin-coated on their surfaces. It was found that the gold nanorod array with a larger diameter can enhance the second harmonic generation (SHG) of ZnO nanofilm by a factor of 27.0, while it is about 7.3 for the smaller gold nanorod array. Theoretical simulations indicate that such stronger enhancement of the larger vertical gold nanorod array compared with the smaller one is due to its stronger scattering ability and greater extent of near-field enhancement at SHG fundamental wavelength. Our work shows that the diameter of gold nanorods is also an important factor to be considered in realizing strong plasmon enhancement of vertically aligned gold nanorod arrays.

scholarly journals Biomedical Applications of Nanomaterials: Diagnosis and Therapy of Thrombotic Disorders

2017 ◽  
Vol 53 (01) ◽  
pp. 036-040
Author(s):  
D. Dash
Keyword(s):  
Gold Nanorods ◽  
Photothermal Therapy ◽  
Biomedical Applications ◽  
Near Infrared ◽  
Infrared Laser ◽  
Coronary Risk ◽  
Innovative Strategy ◽  
Diagnosis And Therapy ◽  
Metallic Nanomaterials

ABSTRACTWe have employed unique properties of carbon-based as well as metallic nanomaterials to develop diagnostic / therapeutic devices targeted against thrombotic disorders. We have designed a novel graphene-based biosensor that can detect individuals with high coronary risk. Further, we describe an innovative strategy to ablate pathological thrombus in situ employing near-infrared laser-irradiated gold nanorods (photothermal therapy).

scholarly journals Enhanced Delivery of Thermoresponsive Polymer-Based Medicine into Tumors by Using Heat Produced from Gold Nanorods Irradiated with Near-Infrared Light

Cancers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 5005
Author(s):  
Kohei Sano ◽  
Yumi Ishida ◽  
Toshie Tanaka ◽  
Tatsuya Mizukami ◽  
Tomono Nagayama ◽  
...  
Keyword(s):  
Gold Nanorods ◽  
Near Infrared ◽  
Drug Carrier ◽  
Light Irradiation ◽  
Infrared Light ◽  
Solution Temperature ◽  
Dependent Manner ◽  
Thermoresponsive Polymer ◽  
Tumor Bearing ◽  
Nir Light

The aim of this study was to establish a drug delivery system (DDS) for marked therapy of tumors using a thermoresponsive polymer, polyoxazoline (POZ). The effectiveness of the following was investigated: (i) the delivery of gold nanorods (GNRs) to tumor tissues, (ii) heat production of GNR upon irradiation with near-infrared (NIR) light, and (iii) high accumulation of an intravenously injected radiolabeled POZ as a drug carrier in tumors by sensing heat produced by GNRs. When the GNR solution was irradiated with NIR light (808 nm), the solution temperature was increased both in a GNR-concentration-dependent manner and in a light-dose-dependent manner. POZ, with a lower critical solution temperature of 38 °C, was aggregated depending on the heat produced by the GNR irradiated by NIR light. When it was intratumorally pre-injected into colon26-tumor-bearing mice, followed by NIR light irradiation (GNR+/Light+ group), the tumor surface temperature increased to approximately 42 °C within 5 min. Fifteen minutes after irradiation with NIR light, indium-111 (111In)-labeled POZ was intravenously injected into tumor-bearing mice, and the radioactivity distribution was evaluated. The accumulation of POZ in the tumor was significantly (approximately 4-fold) higher than that in the control groups (GNR+/without NIR light irradiation (Light–), without injection of GNR (GNR–)/Light+, and GNR–/Light– groups). Furthermore, an in vivo confocal fluorescence microscopy study, using fluorescence-labeled POZ, revealed that uptake of POZ by the tumor could be attributed to the heat produced by GNR. In conclusion, we successfully established a novel DDS in which POZ could be efficiently delivered into tumors by using the heat produced by GNR irradiated with NIR light.

scholarly journals The Effect of Gold Nanorods Clustering on Near-Infrared Radiation Absorption

2018 ◽  
Vol 8 (7) ◽  
pp. 1132 ◽  
Author(s):  
Xi Gu ◽  
Victoria Timchenko ◽  
Guan Heng Yeoh ◽  
Leonid Dombrovsky ◽  
Robert Taylor
Keyword(s):  
Heat Generation ◽  
Gold Nanorods ◽  
Near Infrared ◽  
Volume Fraction ◽  
Resonant Absorption ◽  
Absorption Efficiency ◽  
Maximum Absorption ◽  
Radiation Absorption ◽  
Nir Light ◽  
Rate Of Increase

In this paper, the plasmonic resonant absorption of gold nanorods (GNRs) and GNR solutions was studied both numerically and experimentally. The heat generation in clustered GNR solutions with various concentrations was measured by exposing them to Near Infrared (NIR) light in experiment. Correspondingly, calculations based on the discrete-dipole approximation (DDA) revealed the same relationship between the maximum absorption efficiency and the nanorod orientation for the incident radiation. Additionally, both the plasmonic wavelength and the maximum absorption efficiency of a single nanorod were found to increase linearly with increasing aspect ratio (for a fixed nanorod volume). The wavelength of the surface plasmonic resonance (SPR) was found to change when the gold nanorods were closely spaced. Specifically, both a shift and a broadening of the resonance peak were attained when the distance between the nanorods was set to about 50 nm or less. The absorbance spectra of suspended nanorods at various volume fractions also showed that the plasmonic wavelength of the nanorods solution was at 780 ± 10 nm, which was in good agreement with the computational predictions for coupled side-by-side nanorods. When heated by NIR light, the rate of increase for both the temperature of solution and the absorbed light diminished when the volume fraction of suspended nanorods reached a value of 1.24×10−6. This matches with expectations for a partially clustered suspension of nanorods in water. Overall, this study reveals that particle clustering should be considered to accurately gauge the heat generation of the GNR hyperthermia treatments.

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