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Gold nanoparticles radiation

Alejandro Zamora-Gálvez, Eden Morales-Narváez, Javier Romero, Arben Merkoçi
A new paper-based lateral flow immunoassay configuration was engineered and investigated. The assay is intended for the detection of a model protein in human serum, that is, human immunoglobulin G, with the aim to demonstrate a virtually universal protein detection platform. Once the sample is added in the strip, the analyte is selectively captured by antibody-decorated silica beads (Ab-SiO2) onto the conjugate pad and the sample flows by capillarity throughout the strip until reaching the test line, where a sandwich-like immunocomplex takes place due to the presence of antibody-functionalized QDs (Ab-QDs) onto the test line...
September 11, 2017: Biosensors & Bioelectronics
Rita Mendes, Pedro Pedrosa, João C Lima, Alexandra R Fernandes, Pedro V Baptista
Photothermal Therapy (PTT) impact in cancer therapy has been increasing due to the enhanced photothermal capabilities of a new generation of nanoscale photothermal agents. Among these nanoscale agents, gold nanoshells and nanorods have demonstrated optimal properties for translation of near infra-red radiation into heat at the site of interest. However, smaller spherical gold nanoparticles (AuNPs) are easier to produce, less toxic and show improved photoconversion capability that may profit from the irradiation in the visible via standard surgical green lasers...
September 7, 2017: Scientific Reports
Jian Zhao, Keyao Tu, Yanlei Liu, Yulei Qin, Xiwei Wang, Lifeng Qi, Donglu Shi
Dual surfaced dumbbell-like gold magnetic nanoparticles (Au-Fe3O4) were synthesized for targeted aptamers delivery. Their unique biological properties were characterized as a smart photo-controlled drug carrier. DNA aptamers targeting vascular endothelial growth factor (VEGF) were assembled onto the surface of Au-Fe3O4 by electrostatic absorption. The binding capacity of the nanoparticles with VEGF aptamers was confirmed by gel electrophoresis. The targeted recognization of ovarian cancer cells by the aptamers-functionalized Au-Fe3O4 nanoparticles (Apt-Au-Fe3O4 NPs) was observed by confocal microscopy...
November 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Seongmoon Jung, Wonmo Sung, Sung-Joon Ye
This work aims to develop a Monte Carlo (MC) model for pinhole K-shell X-ray fluorescence (XRF) imaging of metal nanoparticles using polychromatic X-rays. The MC model consisted of two-dimensional (2D) position-sensitive detectors and fan-beam X-rays used to stimulate the emission of XRF photons from gadolinium (Gd) or gold (Au) nanoparticles. Four cylindrical columns containing different concentrations of nanoparticles ranging from 0.01% to 0.09% by weight (wt%) were placed in a 5 cm diameter cylindrical water phantom...
2017: International Journal of Nanomedicine
Ping-Hsiu Wu, Yasuhito Onodera, Yuki Ichikawa, Erinn B Rankin, Amato J Giaccia, Yuko Watanabe, Wei Qian, Takayuki Hashimoto, Hiroki Shirato, Jin-Min Nam
Gold nanoparticles (AuNPs) have recently attracted attention as clinical agents for enhancing the effect of radiotherapy in various cancers. Although radiotherapy is a standard treatment for cancers, invasive recurrence and metastasis are significant clinical problems. Several studies have suggested that radiation promotes the invasion of cancer cells by activating molecular mechanisms involving integrin and fibronectin (FN). In this study, polyethylene-glycolylated AuNPs (P-AuNPs) were conjugated with Arg-Gly-Asp (RGD) peptides (RGD/P-AuNPs) to target cancer cells expressing RGD-binding integrins such as α5- and αv-integrins...
2017: International Journal of Nanomedicine
Guohai Liang, Xudong Jin, Shuxu Zhang, Da Xing
Radiotherapy is a leading treatment approach of cancer therapy. While it is effective in killing tumor cells, it can also cause serious damage to surrounding normal tissue. Targeted radiotherapy with gold nanoparticle-based radiosensitizers is actively being investigated, and considered as a promising means to enhance the efficacy of radiotherapy against tumors under a relatively low and safe radiation dose. In this work, we report a green and one-step strategy to synthesize fluorescent gold nanoclusters by using a commercialized cyclic arginine-glycine-aspartic acid (c(RGDyC)) peptide as the template...
August 16, 2017: Biomaterials
Sang Hee Ahn, Kwangzoo Chung, Jung Wook Shin, Wonjoong Cheon, Youngyih Han, Hee Chul Park, Doo Ho Choi
Gold nanoparticles (GNPs) injected in a body for dose enhancement in radiation therapy are known to form clusters. We investigated the dependence of dose enhancement on the GNP morphology using Monte-Carlo simulations and compared the model predictions with experimental data. The cluster morphology was approximated as a body-centred cubic (BCC) structure by placing GNPs at the 8 corners and the centre of a cube with an edge length of 0.22-1.03 µm in a 4  ×  4  ×  4 µm(3) water-filled phantom...
September 15, 2017: Physics in Medicine and Biology
Md Habban Akhter, Md Rizwanullah, Javed Ahmad, Mohamed Jawed Ahsan, Md Ali Mujtaba, Saima Amin
Cancer has been growing nowadays consequently high number of death ascertained worldwide. The medical intervention involves chemotherapy, radiation therapy and surgical removal. This conventional technique lacking targeting potential and harm the normal cells. In drug treatment regimen, the combination therapy is preferred than single drug treatment module due to higher internalization of chemotherapeutics in the cancer cells both by enhance permeation retention effect and by direct cell apoptosis. The cancer therapeutics involves different methodologies of delivering active moiety to the target site...
August 22, 2017: Artificial Cells, Nanomedicine, and Biotechnology
Doyeon Bang, Eun-Jung Jo, SoonGweon Hong, Ju-Young Byun, Jae Young Lee, Min-Gon Kim, Luke P Lee
Frequency upconversion activated with Lanthanide has attracted attention in various real-world applications, because it is far simpler and more efficient than traditional nonlinear susceptibility-based frequency upconversion, such as second harmonic generation. However, the quantum yield of frequency upconversion of Lanthanide-based upconversion nanoparticles remains inefficient for practical applications, and spatial control of upconverted emission is not yet developed. To overcome this limitation, we developed asymmetric hetero-plasmonic nanoparticles (AHPNs) consisting of plasmonic antennae in nanocrescent shapes on the Lanthanide-based upconversion nanoparticle (UC) for efficiently delivering excitation light to the UC core by nanofocusing of light and generating asymmetric frequency upconverted emission concentrated toward the tip region...
August 21, 2017: Nano Letters
Ningning Ma, Peidang Liu, Nongyue He, Ning Gu, Fu-Gen Wu, Zhan Chen
A major challenge to achieve effective X-ray radiation therapy is to use a relatively low and safe radiation dose. Various radiosensitizers, which can significantly enhance the radiotherapeutic performance, have been developed. Gold-based nanomaterials, as a new type of nanoparticle-based radiosensitizers, have been extensively used in researches involving cancer radiotherapy. However, the cancer therapeutic effect using the gold nanoparticle-based radiotherapy is usually not significant because of the low cellular uptake efficiency and the autophagy-inducing ability of these gold nanomaterials...
September 20, 2017: ACS Applied Materials & Interfaces
Bing Fu, Benjamin P Isaacoff, Julie S Biteen
Plasmonic nanoparticles (NPs) enhance the radiative decay rate of adjacent dyes and can significantly increase fluorescence intensity for improved spectroscopy. However, the NP nanoantenna complicates super-resolution imaging by introducing a mislocalization between the emitter position and its super-resolved emission position. The mislocalization magnitude depends strongly on the dye/NP coupling geometry. It is therefore crucial to quantify mislocalization to recover the actual emitter position in a coupled system...
August 18, 2017: ACS Nano
Swarup Roy, Shailendra K Saxena, Suryakant Mishra, Priyanka Yogi, P R Sagdeo, Rajesh Kumar
In the featured work interaction between biosynthesized gold nanoparticles (GNP) and lysozyme (Lys) has been studied using multi-spectroscopic approach. A moderate association constant (Kapp) of 2.66×10(4)L/mol has been observed indicative of interactive nature. The binding constant (Kb) was 1.99, 6.30 and 31.6×10(4)L/mol at 291, 298 and 305K respectively and the number of binding sites (n) was found to be approximately one. Estimated values of thermodynamic parameters (Enthalpy change, ΔH=141.99kJ/mol, entropy change, ΔS=570J/mol/K, Gibbs free energy change, ΔG=-27...
August 8, 2017: Journal of Photochemistry and Photobiology. B, Biology
Eduardo Ortega, Jesús Cantu-Valle, Germán Plascencia-Villa, Sandra Vergara, Fernando Mendoza-Santoyo, Alejandra Londono-Calderon, Ulises Santiago, Arturo Ponce
In the current work, irregular morphology of Staphylococcus aureus bacteria has been visualized by phase retrieval employing off-axis electron holography (EH) and 3D reconstruction electron tomography using high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM). Bacteria interacting with gold nanoparticles (AuNP) acquired a shrunken or irregular shape due to air dehydration processing. STEM imaging shows the attachment of AuNP on the surface of cells and suggests an irregular 3D morphology of the specimen...
August 11, 2017: Microscopy Research and Technique
Jaber Beik, Sara Khademi, Neda Attaran, Saeed Sarkar, Ali Shakeri-Zadeh, Habib Ghaznavi, Hossein Ghadiri
BACKGROUND: Gold nanoparticle (AuNP), owing to its elegant physicochemical properties, has been recently introduced as a promising theranostic nanoparticle. Folic acid is a necessary vitamin for cell proliferation and cancer cells highly require such an essential molecule to be replicated. Accordingly, surface functionalization of AuNP with folic acid may offer great potentials for development of a new nanotechnology based strategy to increase the efficiency of cancer diagnosis and therapy...
August 10, 2017: Current Medicinal Chemistry
Nadeem M S Nagi, Yasir A M Khair, Ahmed M E Abdalla
Radiotherapy is the ionizing radiation used for treatment of cancer and other diseases. Although radiotherapy is the major treatment for cancer, a lot of patients do not undergo radiation due to associated risks such as radiation pneumonitis, cardiovascular complications, development of secondary tumor, and lymphedema. However, the advantages of nanotechnology provide a unique potential to enhance radiotherapeutic performance, in particular by utilizing gold nanoparticles (Au NPs). In this review, we briefly describe the current direction of research towards the use of Au NPs for radiotherapeutic enhancement, combination, monitoring and in side effect reductions...
August 9, 2017: Japanese Journal of Radiology
Ismail Ocsoy, Sadi Yusufbeyoglu, Vedat Yılmaz, Eric S McLamore, Nilay Ildız, Ahmet Ülgen
In this work, we report the development of DNA aptamer-functionalized gold nanoparticles (Apt@Au NPs) and gold nanorods (Apt@Au NRs) for inactivation of Methicillin-resistant Staphylococcus aureus (MRSA) with targeted photothermal therapy (PTT). Although both Apt@Au NPs and Apt@Au NRs specifically bind to MRSA cells, Apt@Au NPs and Apt@Au NRs inactivated ∼5% and over 95% of the cells,respectively through PTT. This difference in inactivation was based on the relatively high longitudinal absorption of near-infrared (NIR) radiation and strong photothermal conversion capability for the Apt@Au NRs compared to the Apt@Au NPs...
July 25, 2017: Colloids and Surfaces. B, Biointerfaces
Dawid Piątkowski, Mikołaj K Schmidt, Magdalena Twardowska, Marcin Nyk, Javier Aizpurua, Sebastian Maćkowski
We experimentally demonstrate strong spectral selectivity of plasmonic interaction that occurs between α-NaYF₄:Er(3+)/Yb(3+) nanocrystals, which feature two emission bands, and spherical gold nanoparticles, with plasmon frequency resonant with one of the emission bands. Spatially-resolved luminescence intensity maps acquired for individual nanocrystals, together with microsecond luminescence lifetime images, show two qualitatively different effects that result from the coupling between plasmon excitations in metallic nanoparticles and emitting states of the nanocrystals...
August 4, 2017: Materials
Jayasmita Jana, Teresa Aditya, Mainak Ganguly, Shyamal Kumar Mehetor, Tarasankar Pal
Metal enhanced fluorescence of carbon dots has been reported in aqueous solution. Moderately fluorescing carbon dots (λex=360nm and λem=440nm) of 6-8nm diameters (CDA) have been synthesized from freshly prepared aqueous ascorbic acid solution under modified hydrothermal treatment. The CDA fluorescence is quenched at the close proximity with gold nanoparticles (AuNPs). Here, a substrate specific near-field electric field distribution is pronounced. Anticipating distance dependent fluorescence enhancement phenomenon, long-chain aliphatic thiol capped AuNPs are introduced to improve fluorescence of moderately fluorescing CDAs...
January 5, 2018: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Andrea Mescola, Claudio Canale, Despina Fragouli, Athanassia Athanassiou
The localized formation of gold nanostructures with controlled size and shape on chitosan films doped with gold precursor upon electromagnetic irradiation of various types is demonstrated here. Such controlled formation is achieved by tuning the wavelength, the energy and the interaction time of the radiation with the composite films. In particular, the use of a single UV nanosecond laser pulse results in the formation of gold sub-micron platelets with specific crystal structure, while increasing the number of pulses, further precursor reduction and photofragmentation induce the formation of gold nanoparticles...
August 1, 2017: Nanotechnology
Seung-Jun Seo, Jae-Kun Jeon, Sung-Mi Han, Jong-Ki Kim
PURPOSE: The Coulomb nanoradiator (CNR) effect produces the dose enhancement effects from high-Z nanoparticles under irradiation with a high-energy ion beam. To gain insight into the radiation dose and biological significance of the CNR effect, the enhancement of reactive oxygen species (ROS) production from iron oxide or gold NPs (IONs or AuNPs, respectively) in water was investigated using traversing proton beams. METHODS AND MATERIALS: The dependence of nanoradiator-enhanced ROS production on the atomic Z value and proton energy was investigated...
August 16, 2017: International Journal of Radiation Biology
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