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Gold nanoparticles radiation

Wonmo Sung, Sung-Joon Ye, Aimee L McNamara, Stephen J McMahon, James Hainfeld, Jungwook Shin, Henry M Smilowitz, Harald Paganetti, Jan Schuemann
The radiosensitization effect of gold nanoparticles (GNPs) has been demonstrated both in vitro and in vivo in radiation therapy. The purpose of this study was to systematically assess the biological effectiveness of GNPs distributed in the extracellular media for realistic cell geometries. TOPAS-nBio simulations were used to determine the nanometre-scale radial dose distributions around the GNPs, which were subsequently used to predict the radiation dose response of cells surrounded by GNPs. MDA-MB-231 human breast cancer cells and F-98 rat glioma cells were used as models to assess different cell geometries by changing (1) the cell shape, (2) the nucleus location within the cell, (3) the size of GNPs, and (4) the photon energy...
April 21, 2017: Nanoscale
Chulhwan Hwang, Ja Mee Kim, JungHoon Kim
The purpose of this study was to analyse the effects of the type, concentration, and nanoparticle diameter of dose enhancement materials on the dose enhancement of low- and high-energy megavoltage (MV) X-rays acquired from a medical linear accelerator using Monte Carlo simulation. Monte Carlo simulation was performed with the Monte Carlo N-Particle Transport (MCNPX) code, using the energy spectrum of the linear accelerator and a mathematical Snyder head phantom. A 5-cm-diameter virtual tumour was defined in the centre of the phantom...
April 17, 2017: Journal of Radiation Research
Ningning Ma, Fu-Gen Wu, Xiaodong Zhang, Yao-Wen Jiang, Hao-Ran Jia, Hong-Yin Wang, Yan-Hong Li, Peidang Liu, Ning Gu, Zhan Chen
The shape effect of gold (Au) nanomaterials on the efficiency of cancer radiotherapy has not been fully elucidated. To address this issue, Au nanomaterials with different shapes but similar average size (∼50 nm) including spherical gold nanoparticles (GNPs), gold nanospikes (GNSs), and gold nanorods (GNRs) were synthesized and functionalized with poly(ethylene glycol) (PEG) molecules. Although all of these Au nanostructures were coated with the same PEG molecules, their cellular uptake behavior differed significantly...
April 10, 2017: ACS Applied Materials & Interfaces
Nikolaos M Dimitriou, George Tsekenis, Evangelos C Balanikas, Athanasia Pavlopoulou, Melina Mitsiogianni, Theodora Mantso, George Pashos, Andreas G Boudouvis, Ioannis N Lykakis, Georgios Tsigaridas, Mihalis I Panayiotidis, Vassilios Yannopapas, Alexandros G Georgakilas
Considering both cancer's serious impact on public health and the side effects of cancer treatments, strategies towards targeted cancer therapy have lately gained considerable interest. Employment of gold nanoparticles (GNPs), in combination with ionizing and non-ionizing radiations, has been shown to improve the effect of radiation treatment significantly. GNPs, as high-Z particles, possess the ability to absorb ionizing radiation and enhance the deposited dose within the targeted tumors. Furthermore, they can convert non-ionizing radiation into heat, due to plasmon resonance, leading to hyperthermic damage to cancer cells...
March 16, 2017: Pharmacology & Therapeutics
Mihaela Ghita, Stephen J McMahon, Laura E Taggart, Karl T Butterworth, Giuseppe Schettino, Kevin M Prise
Gold nanoparticles (GNPs) have been demonstrated as effective radiosensitizing agents in a range of preclinical models using broad field sources of various energies. This study aimed to distinguish between these mechanisms by applying subcellular targeting using a soft X-ray microbeam in combination with GNPs. DNA damage and repair kinetics were determined following nuclear and cytoplasmic irradiation using a soft X-ray (carbon K-shell, 278 eV) microbeam in MDA-MB-231 breast cancer and AG01522 fibroblast cells with and without GNPs...
March 16, 2017: Scientific Reports
Somayeh Sadat Mehrnia, Bijan Hashemi, Seyed Javad Mowla, Azim Arbabi
Gold nanoparticles (GNPs) have been applied as radiosensitizer in radiotherapy. Limited reports have shown that GNPs may be effective as a dose enhancer agent for electron radiation therapy. Some Monte Carlo Simulation studies have shown that selecting suitable size of GNPs and electron energies are critical for effective dose enhancement. The aim of this study was to assess possible radiosensitization effect of GNPs on cancer cell treated with 4MeV electron beams. Approximately 10nm GNPs were synthesized and characterized by electron microscope and dynamic light scattering...
March 2017: Physica Medica: PM
Sherif M Gadoue, Dolla Toomeh, Piotr Zygmanski, Erno Sajo
Gold nanoparticle (GNP) radiotherapy has recently emerged as a promising modality in cancer treatment. The use of high atomic number nanoparticles can lead to enhanced radiation dose in tumors due to low-energy leakage electrons depositing in the vicinity of the GNP. A single metric, the dose enhancement ratio has been used in the literature, often in substantial disagreement, to quantify the GNP's capacity to increase local energy deposition. This 1D approach neglects known sources of dose anisotropy and assumes that one average value is representative of the dose enhancement...
March 8, 2017: Nanomedicine: Nanotechnology, Biology, and Medicine
Hakim Belmouaddine, Minghan Shi, Paul-Ludovic Karsenti, Ridthee Meesat, Léon Sanche, Daniel Houde
The "cold" low density plasma channels generated by the filamentation of powerful femtosecond laser pulses in aqueous solutions constitute a source of dense ionization. Here, we probed the radiation-assisted chemistry of water triggered by laser ionization via the radical-mediated synthesis of nanoparticles in gold chloride aqueous solutions. We showed that the formation of colloidal gold originates from the reduction of trivalent ionic gold initially present in solution by the reactive radicals (e.g. hydrated electrons) produced upon the photolysis of water...
March 6, 2017: Physical Chemistry Chemical Physics: PCCP
Zohre Rezaee, Ali Yadollahpour, Vahid Bayati, Fereshteh Negad Dehbashi
BACKGROUND AND OBJECTIVE: Radiation therapy (RT) is the gold standard treatment for more than half of known tumors. Despite recent improvements in RT efficiency, the side effects of ionizing radiation (IR) in normal tissues are a dose-limiting factor that restricts higher doses in tumor treatment. One approach to enhance the efficiency of RT is the application of radiosensitizers to selectively increase the dose at the tumor site. Gold nanoparticles (GNPs) and electroporation (EP) have shown good potential as radiosensitizers for RT...
2017: International Journal of Nanomedicine
Yurii N Barabanenkov, Mikhail Yu Barabanenkov
A new general formula is presented for a collective extinction cross section of a dielectric or a metallic nanoparticle ensemble in terms of incident electric field work on currents excited inside particles. The formula is obtained by identical transformation of the well-known expression for the summing power of electromagnetic field energy losses caused by particle ensemble scattering and absorption. The derived formula is applied to the problem of radiation losses at electromagnetic excitation transfer along a straight chain of particles...
March 1, 2017: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
H L Byrne, Y Gholami, Z Kuncic
The addition of gold nanoparticles within target tissue (i.e. a tumour) to enhance the delivered radiation dose is a well studied radiotherapy treatment strategy, despite not yet having been translated into standard clinical practice. While several studies have used Monte Carlo simulations to investigate radiation dose enhancement by Auger electrons emitted from irradiated gold nanoparticles, none have yet considered the effects due to escaping fluorescence photons. Geant4 was used to simulate a water phantom containing 10 mg ml(-1) uniformly dispersed gold (1% by mass) at 5 cm depth...
April 21, 2017: Physics in Medicine and Biology
Chris Y Y Yu, Huae Xu, Shenglu Ji, Ryan T K Kwok, Jacky W Y Lam, Xiaolin Li, Sunil Krishnan, Dan Ding, Ben Zhong Tang
The first mitochondrion-anchoring photosensitizer that specifically generates singlet oxygen ((1) O2 ) in mitochondria under white light irradiation that can serve as a highly effective radiosensitizer is reported here, significantly sensitizing cancer cells to ionizing radiation. An aggregation-induced emission luminogen (AIEgen), namely DPA-SCP, is rationally designed with α-cyanostilbene as a simple building block to reveal AIE, diphenylamino (DPA) group as a strong electron donating group to benefit red emission and efficient light-controlled (1) O2 generation, as well as a pyridinium salt as the targeting moiety to ensure specific mitochondrial localization...
April 2017: Advanced Materials
Elisabetta Gargioni, Florian Schulz, Annette Raabe, Susanne Burdak-Rothkamm, Thorsten Rieckmann, Kai Rothkamm
Despite considerable progress in (I) our understanding of the aetiopathology of head and neck cancer and (II) the precise delivery of radiotherapy, long-term survival rates for many patients with head and neck cancer remain disappointingly low. Over the past years, gold nanoparticles (NP) have emerged as promising radiation dose enhancers. In a recent study published in Nanoscale, Popovtzer et al. have used gold NP coated with an antibody against the epidermal growth factor receptor (EGFR) in an attempt to enhance radiation-induced tumour cell killing in a head and neck cancer xenograft model...
December 2016: Annals of Translational Medicine
Alexandre Detappe, Eloise Thomas, Mark W Tibbitt, Sijumon Kunjachan, Oksana Zavidij, Nishita Parnandi, Elizaveta Reznichenko, François Lux, Olivier Tillement, Ross Berbeco
Selective killing of cancer cells while minimizing damage to healthy tissues is the goal of clinical radiation therapy. This therapeutic ratio can be improved by image-guided radiation delivery and selective radiosensitization of cancer cells. Here, we have designed and tested a novel trimodal theranostic nanoparticle made of bismuth and gadolinium for on-site radiosensitization and image contrast enhancement to improve the efficacy and accuracy of radiation therapy. We demonstrate in vivo magnetic resonance (MR), computed tomography (CT) contrast enhancement, and tumor suppression with prolonged survival in a non-small cell lung carcinoma model during clinical radiation therapy...
March 8, 2017: Nano Letters
D Brivio, P L Nguyen, E Sajo, W Ngwa, P Zygmanski
We investigate via Monte Carlo simulations a new (125)I brachytherapy treatment technique for high-risk prostate cancer patients via injection of Au nanoparticle (AuNP) directly into the prostate. The purpose of using the nanoparticles is to increase the therapeutic index via two synergistic effects: enhanced energy deposition within the prostate and simultaneous shielding of organs at risk from radiation escaping from the prostate. Both uniform and non-uniform concentrations of AuNP are studied. The latter are modeled considering the possibility of AuNP diffusion after the injection using brachy needles...
March 7, 2017: Physics in Medicine and Biology
S R Bhattarai, P J Derry, K Aziz, P K Singh, A M Khoo, A S Chadha, A Liopo, E R Zubarev, S Krishnan
In the past decade, there has been considerable interest in radiosensitization using gold nanoparticles that accumulate specifically in cancerous tissue while sparing normal tissues. Despite this interest, it remains unclear which nanoparticle morphologies, cellular uptake, or cytoplasmic distribution elicit optimal radiosensitization. We introduce gold nanotriangles (AuNTs) as a possible X-ray radiotherapy sensitizer. In this study, we first explored a large-scale synthetic method for the production of high quality monodisperse AuNTs...
April 20, 2017: Nanoscale
Jafar Fattahi-Asl, Mojtaba Karbalaee, Masoud Sanatizadeh, Payam Amini
OBJECTIVE: The aim of this study was to compare the effects of radiofrequency radiation (RF) in synergism with gold (Au) and silver (Ag) nanoparticles (NPs) on the survival fraction of human normal kidney (HNK) and human embryonic kidney (HEK) cells. MATERIALS AND METHODS: HNK and HEK cells were divided into three groups as control, 1 and 2 h/day-irradiated groups for 8 days. To compare the effects of RF in the presence of Au-NPs and Ag-NPs, the cells were incubated with NPs during the irradiation...
October 2016: International Journal of Pharmaceutical Investigation
Ying Chen, Yonghui Wu, Jining Gao, Zihao Zhang, Linjie Wang, Xi Chen, Junwei Mi, Yuanjiang Yao, Dongwei Guan, Bing Chen, Jianwu Dai
Skin injuries caused by burns or radiation remain a serious concern in terms of clinical therapy. Because of the damage to the epidermis or dermis, angiogenesis is needed to repair the skin. Vascular endothelial growth factor (VEGF) is one of the most effective factors for promoting angiogenesis and preventing injury progression, but the delivery of VEGF to lesion sites is limited by the skin barrier. Recently, gold nanoparticle (AuNP)-mediated drug delivery into or through the epidermis and dermis has attracted much attention...
February 3, 2017: ACS Applied Materials & Interfaces
F Reynoso, J Munro, S Cho
PURPOSE: To determine the AAPM TG-43 brachytherapy dosimetry parameters of a new titanium-encapsulated Yb-169 source designed to maximize the dose enhancement during gold nanoparticle-aided radiation therapy (GNRT). METHODS: An existing Monte Carlo (MC) model of the titanium-encapsulated Yb-169 source, which was described in the current investigators' published MC optimization study, was modified based on the source manufacturer's detailed specifications, resulting in an accurate model of the titanium-encapsulated Yb-169 source that was actually manufactured...
June 2016: Medical Physics
L Wang
Lihong V. Wang: Photoacoustic tomography (PAT), combining non-ionizing optical and ultrasonic waves via the photoacoustic effect, provides in vivo multiscale functional, metabolic, and molecular imaging. Broad applications include imaging of the breast, brain, skin, esophagus, colon, vascular system, and lymphatic system in humans or animals. Light offers rich contrast but does not penetrate biological tissue in straight paths as x-rays do. Consequently, high-resolution pure optical imaging (e.g., confocal microscopy, two-photon microscopy, and optical coherence tomography) is limited to penetration within the optical diffusion limit (∼1 mm in the skin)...
June 2016: Medical Physics
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