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localized-surface-plasmon-resonance
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Gold@Silver@Gold Core double-shell nanoparticles: synthesis and aggregation-enhanced two-photon photoluminescence evaluation
, Article Plasmonics ; Volume 15, Issue 2 , 2020 , Pages 409-416 ; Sadrnezhaad, S. K ; Sharif University of Technology
Springer
2020
Abstract
A facile, straightforward, and low-cost method is proposed to synthesize gold@silver@gold core double-shell nanoparticles. The technique is a seed-mediated growth protocol that contains four steps of (1) gold seed synthesis, (2) gold seed growth, (3) silver layer coating through silver salt reduction, and (4) gold layer deposition via gold precursor reduction. The prepared nanoparticles had a narrow size distribution and the average particle size of 28 ± 1 nm. Cysteine was introduced to the nanoparticles solution as a coupling agent to assemble nanoparticles. Aggregation-induced two-photon photoluminescence enhancement of three types assembled nanoparticles, i.e., gold@silver@gold,...
Fabrication localized surface plasmon resonance sensor chip of gold nanoparticles and detection lipase-osmolytes interaction
, Article Applied Surface Science ; Vol. 314, issue , 2014 , Pages 138-144 ; ISSN: 01694332 ; Hoornam, S ; Vesaghi, M. A ; Ranjbar, B ; Azizi, A ; Mobasheri, H ; Sharif University of Technology
Abstract
Co-deposition of RF-sputtering and RF-PECVD from acetylene gas and Au target were used to prepare sensor chip of gold nanoparticles (Au NPs). Deposition conditions were optimized to reach a Localized Surface Plasmon Resonance (LSPR) sensor chip of Au NPs with particle size less than 10 nm. The RF power was set at 180 W and the initial gas pressure was set at 0.035 mbar. Transmission Electron Microscopy (TEM) images and Atomic Force Microscopy (AFM) data were used to investigate particles size and surface morphology of LSPR sensor chip. The Au and C content of the LSPR sensor chip of Au NPs was obtained from X-ray photoelectron spectroscopy (XPS). The hydrogenated amorphous carbon (a-C:H)...
Synthesis & Characterization of Au-HKUST-1 Nanocomposite and Evaluation of Plasmonic Properties of Gold Nanoparticles in this Nanocomposite
, M.Sc. Thesis Sharif University of Technology ; Madaah Hosseini, Hamid Reza (Supervisor)
Abstract
In the past few years, many research works on the controllable integration of metal nanoparticles and metal-organic frameworks were done, since the obtained composite material shows a synergism effect in catalysis and photocatalysis, drug delivery applications, gas, and energy storage, as well as sensing. For the first time, in this study, we employed template-assisted growth to synthesize Au-HKUST-1 Nanocomposite. XRD analysis entirely confirms that employing this strategy in synthesizing Au-HKUST-1 was wholly successful, and the plasmonic properties of this nanostructure were studied via UV-visible spectroscopy. In the course of synthesis, gold nanoparticles with 70nm diameter were...
Exploitation of n-gene of sars-cov-2 to develop a new rapid assay by ASOs@AuNPs
, Article Analytical Chemistry ; Volume 94, Issue 39 , 2022 , Pages 13616-13622 ; 00032700 (ISSN) ; Samadikhah, H. R ; Hosseinkhani, S ; Sharif University of Technology
American Chemical Society
2022
Abstract
A naked-eye (equipment-free), label-free (cost-effective), and RNA extraction-free (to speed up) method for SARS-CoV-2 (as a case study of RNA viruses) detection is developed. Here, the DNA is being used as a template for in situ formation of anisotropic gold nanoparticles (AuNPs) without any chemical modification or DNA labeling. In this study, synthesized AuNPs for the direct detection of N-gene (nucleocapsid phosphoprotein) of SARS-CoV-2 are exploited. To this aim, antisense oligonucleotides (ASOs) with an extra poly guanine tail (G12) were designed. Thus, in the presence of its viral target RNA gene and ASOs@AuNPs-RNA hybridization, there was a red shift in its localized surface plasmon...
A novel photometric glucose biosensor based on decolorizing of silver nanoparticles
, Article Sensors and Actuators, B: Chemical ; Volume 158, Issue 1 , November , 2011 , Pages 185-189 ; 09254005 (ISSN) ; Hormozi Nezhad, M. R ; Khodaveisi, J ; Dashti, R ; Sharif University of Technology
2011
Abstract
A novel glucose biosensor based on chromophore (silver nanoparticles) decolorizing for the photometric determination of glucose was developed. Silver nanoparticles are directly synthesized in the sol-gel matrix by a one-step method based on the reduction of the inorganic precursor AgNO3 and were used for the preparation, characterization and calibration of a highly sensitive and cost-effective localized surface plasmon resonance-based glucose biosensor. In the presence of glucose oxidase (GOx) and due to the enzyme-substrate (glucose) reaction, H2O2 was produced and silver nanoparticles in the sol-gel glass have the ability for the decomposition of hydrogen peroxide. Due to the degradation...
Artificial neural network assisted kinetic spectrophotometric technique for simultaneous determination of paracetamol and p-aminophenol in pharmaceutical samples using localized surface plasmon resonance band of silver nanoparticles
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 138 , March , 2015 , Pages 474-480 ; 13861425 (ISSN) ; Dadfarnia, S ; Haji Shabani, A. M ; Rohani Moghadam, M ; Hormozi Nezhad, M. R ; Sharif University of Technology
Elsevier
2015
Abstract
Spectrophotometric analysis method based on the combination of the principal component analysis (PCA) with the feed-forward neural network (FFNN) and the radial basis function network (RBFN) was proposed for the simultaneous determination of paracetamol (PAC) and p-aminophenol (PAP). This technique relies on the difference between the kinetic rates of the reactions between analytes and silver nitrate as the oxidizing agent in the presence of polyvinylpyrrolidone (PVP) which is the stabilizer. The reactions are monitored at the analytical wavelength of 420 nm of the localized surface plasmon resonance (LSPR) band of the formed silver nanoparticles (Ag-NPs). Under the optimized conditions, the...
Development of a novel method for determination of mercury based on its inhibitory effect on horseradish peroxidase activity followed by monitoring the surface plasmon resonance peak of gold nanoparticles
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 153 , 2016 , Pages 709-713 ; 13861425 (ISSN) ; Haji Shabani, A. M ; Dadfarnia, S ; Rohani Moghadam, M. R ; Hormozi Nezhad, M. R ; Sharif University of Technology
Elsevier
Abstract
A highly sensitive and simple indirect spectrophotometric method has been developed for the determination of trace amounts of inorganic mercury (Hg2 +) in aqueous media. The method is based on the inhibitory effect of Hg2 + on the activity of horseradish peroxidase (HRP) in the oxidation of ascorbic acid by hydrogen peroxide followed by the reduction of Au3 + to Au-NPs by unreacted ascorbic acid and the measurement of the absorbance of localized surface plasmon resonance (LSPR) peak of gold nanoparticles (at 530 nm) which is directly proportional to the concentration of Hg2 +. Under the optimum conditions, the calibration curve was linear in the concentration range of 1-220 ng mL- 1. Limits...
Optical Properties of Dimeric Metal Nanoparticles (Gold and Silver) Connected by Conductive Bridge
, M.Sc. Thesis Sharif University of Technology ; Sadighi Bonabi, Rasoul (Supervisor)
Abstract
Over the past two decades, scientists have been intensely interested in the development of metallic nanostructures for their applications in industry and medicine due to their attractive optical properties resulting from surface-localized plasmon resonance (LSPR).In this Thesis, plasmonic resonance modes in bridge dimer (Gold and Silver) are numerically investigated. Without the junction, A high-energy resonant mode called the bonding dimer plasmon (BDP) mode appears in the optical spectrum of the dimer, which is caused by the coupling of each of the nanoparticle plasmon modes. But in bridge dimer, two resonances called screened bonding dimer plasmon mode (SBDP) and charge transfer plasmon...
Localized surface plasmon resonance sensor for simultaneous kinetic determination of peroxyacetic acid and hydrogen peroxide
, Article Analytica Chimica Acta ; Volume 762 , 2013 , Pages 87-93 ; 00032670 (ISSN) ; Hormozi Nezhad, M. R ; Khodaveisi, J ; Dashti, R ; Sharif University of Technology
2013
Abstract
A new sensor for simultaneous determination of peroxyacetic acid and hydrogen peroxide using silver nanoparticles (Ag-NPs) as a chromogenic reagent is introduced. The silver nanoparticles have the catalytic ability for the decomposition of peroxyacetic acid and hydrogen peroxide; then the decomposition of them induces the degradation of silver nanoparticles. Hence, a remarkable change in the localized surface plasmon resonance absorbance strength could be observed. Spectra-kinetic approach and artificial neural network was applied for the simultaneous determination of peroxyacetic acid and hydrogen peroxide. Linear calibration graphs were obtained in the concentration range of (8.20×10-5 to...
CO gas sensor properties of Cu@CuO core-shell nanoparticles based on localized surface plasmon resonance
, Article Journal of Physical Chemistry C ; Volume 115, Issue 45 , 2011 , Pages 22126-22130 ; 19327447 (ISSN) ; Zahrabi, H ; Saani, M. H ; Vesaghi, M. A ; Sharif University of Technology
2011
Abstract
Hexagonal array of Cu@CuO core-shell nanoparticles (NPs) on the a-C:H thin film was prepared by codeposition of RF-sputtering and RF-PECVD. The trace of hexagonal NPs supperlattice was recognized by AFM image and XRD result. On the basis of localized surface plasmon resonance (LSPR) of core-shell NPs, the prepared array detected a low flow rate of CO gas at room temperature. XPS results indicate that the surface of Cu@CuO core-shell NPs have no chemical reaction with CO molecule. The physical absorption of CO molecule on the surface of Cu@CuO core-shell NPs increases the LSPR absorbance and causes a red shift in LSPR wavelength. These experimental results are in agreement with Mie theory...
Fabrication and characterization and biosensor application of gold nanoparticles on the carbon nanotubes
, Article Applied Surface Science ; Volume 355 , November , 2015 , Pages 1175-1179 ; 01694332 (ISSN) ; Aghababaie, N ; Mobasheri, H ; Zand Salimi, K ; Akbarzadeh Pasha, M ; Vesaghi, M. A ; Sharif University of Technology
Elsevier
2015
Abstract
Gold nanoparticles (Au NPs) were synthesized by co-deposition of RF-sputtering and RF-PECVD from acetylene gas and Au target on the carbon nanotubes (CNTs). The CNTs were prepared by thermal chemical vapor deposition (TCVD) and Pd nanoparticles catalyst. TEM image shows that high-density and uniform distribution of Au NPs were grown on the CNTs. XRD analysis indicates that Au NPs have fcc crystal structure and CNTs have a good graphite structure. Raman spectroscopy results suggest that our sample includes double-walled CNTs. It is resulted that intensity of D-band reduces and G-band intensity raises and radial breathing mode (RBM) is changed by immobilizing of Au NPs on the CNTs. Raman...
High-performance UV‐Vis-NIR photodetectors based on plasmonic effect in Au nanoparticles/ZnO nanofibers
, Article Applied Surface Science ; Volume 483 , 2019 , Pages 1110-1117 ; 01694332 (ISSN) ; Arab Bafrani, H ; Naseri, A ; Moshfegh, A. Z ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this study, UV‐Vis-NIR photodetectors based on decorated ZnO nanofibers (NFs) with optimized coverage of Au nanoparticles (NPs) fabricated via combined simple electrospinning and sputtering techniques are introduced. The effect of different coverages of Au NPs resulted from different Au nominal layer thicknesses on the morphology and optical properties of the ZnO fibers are investigated through various characterization methods. It is discovered that 4 nm Au nominal thickness provides the highest UV on/off ratio (~460), responsivity (~332 A/W), detectivity (~2.93×10 11 Jones) as well as faster rise and decay times as compared to pure ZnO nanofibers. A broad spectral response from UV to NIR...
Synergistic enhancement of photocatalytic antibacterial effects in high-strength aluminum/TiO2 nanoarchitectures
, Article Ceramics International ; Volume 46, Issue 15 , October , 2020 , Pages 24267-24280 ; Sarraf, M ; Dabbagh, A ; Nasiri Tabrizi, B ; Paria, S ; Banihashemian, S. M ; Bushroa, A. R ; Faraji, G ; Tsuzuki, T ; Madaah Hosseini, H. R ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Unlike gold and silver, aluminum shows a localized surface plasmon resonance (LSPR) over a wide spectral range from ultraviolet (UV) to the visible region. Herein, we demonstrate a new process to optically couple TiO2 nanotubes (NTs) with a high-strength aluminum substrate, to achieve a synergistic enhancement of photocatalytic antibacterial effects through controlled LSPR of aluminum. The high-strength aluminum substrate was produced by tubular channel angular pressing (TCAP). Their LSPR was tailored through the formation of superficial nano-concave arrays (NCAs) with desired concave diameters. A layer of aligned TiO2 NTs was fabricated on the surface of aluminum nano-concave arrays (Al...
Geometrical optimization for silver nanowire mesh as a flexible transparent conductive electrode
, Article Applied Optics ; Volume 59, Issue 10 , 2020 , Pages 3073-3080 ; Mahdavi, S. M ; Sadrnezhaad, S. K ; Sharif University of Technology
OSA - The Optical Society
2020
Abstract
We report the effect of the geometric parameters on transparency and conductivity in a metallic nanowire mesh as a transparent electrode. Today, indium tin oxide and fluorine-doped tin oxide are used as the transparent electrode for displays and solar cells. Still, there is a definite need for their replacement due to drawbacks such as brittleness, scarcity, and adverse environmental effects. Metallic nanowire mesh is likely the best replacement option, but the main issue is how to find the optimal structure and how to get the best performance. Since the interaction of light with nanowire mesh is complicated, there is no straightforward rule with a simple analytical solution. We developed a...
Localized surface plasmon resonance of Cu@Cu2O coreshell nanoparticles: Absorption, scattering and luminescence
, Article Physica B: Condensed Matter ; Volume 406, Issue 13 , July , 2011 , Pages 2678-2683 ; 09214526 (ISSN) ; Vesaghi, M. A ; Sharif University of Technology
2011
Abstract
By co-deposition via RF-Sputtering and RF-PECVD methods and using Cu target and acetylene gas, we prepared Cu@Cu2O coreshell nanoparticles on the a-C:H thin film at room temperature. Mie absorption of Cu cores, scattering from Cu2O shell and luminescence that rises from carrier transfer in Cu@Cu2O interface were employed to fit the whole range of visible extinction spectrum of these coreshells. From simulation it was found that scattering and luminescence have an important effect on the energy, width and shape of LSPR absorption peak. Shift of LSPR peak is more affected by the dielectric coefficient of shell than Cu core size particularly for Cu core diameter above 4 nm. Also, the LSPR...
Pulsed electrodeposition of gold nanoparticles on fluorine-doped tin oxide glass and absorption-based surface plasmon resonance evaluation
, Article Journal of Nano Research ; Volume 33 , 2015 , Pages 11-26 ; 16625250 (ISSN) ; Sadrnezhaad, S. K ; Sharif University of Technology
Trans Tech Publications Ltd
2015
Abstract
Synthesis and immobilization of Au nanoparticles (AuNPs) was performed on transparent fluorine-doped tin oxide (FTO) substrate by pulse electrodeposition method. The method was cost effective, simple and capable of producing nanoparticles strongly attached to the substrate. Effects of several influencing factors such as duty cycle, pulse frequency, current density, solution concentration, deposition period and annealing procedure on the optical properties of AuNPs-FTO electrode were investigated. AuNPs-FTO electrodes were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and UV-Vis absorption analysis. Controllability...
Morphology, optical and electrical properties of Cu-Ni nanoparticles in a-C:H prepared by co-deposition of RF-sputtering and RF-PECVD
, Article Applied Surface Science ; Volume 258, Issue 2 , 2011 , Pages 727-731 ; 01694332 (ISSN) ; Vesaghi, M. A ; Gelali, A ; Zahrabi, H ; Solaymani, S ; Sharif University of Technology
Abstract
We report optical and electrical properties of Cu-Ni nanoparticles in hydrogenated amorphous carbon (Cu-Ni NPs @ a-C:H) with different surface morphology. Ni NPs with layer thicknesses of 5, 10 and 15 nm over Cu NPs @ a-C:H were prepared by co-deposition of RF-sputtering and RF-Plasma Enhanced Chemical Vapor Deposition (RF-PECVD) from acetylene gas and Cu and Ni targets. A nonmetal-metal transition was observed as the thickness of Ni over layer increases. The surface morphology of the sample was described by a two dimensional (2D) Gaussian self-affine fractal, except the sample with 10 nm thickness of Ni over layer, which is in the nonmetal-metal transition region. X-ray diffraction profile...
Noble metal nanostructures in optical biosensors: basics, and their introduction to anti-doping detection
, Article TrAC - Trends in Analytical Chemistry ; Volume 100 , 2018 , Pages 116-135 ; 01659936 (ISSN) ; Sahandi Zangabad, P ; Mohammadi, H ; Sadroddini, M ; Jafari, Z ; Mahlooji, N ; Abbaspour, S ; Gholami, S ; Ghanbarpoor, M ; Pashazadeh, R ; Beyzavi, A ; Karimi, M ; Hamblin, M. R ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Nanotechnology has illustrated significant potentials in biomolecular-sensing applications; particularly its introduction to anti-doping detection is of great importance. Illicit recreational drugs, substances that can be potentially abused, and drugs with dosage limitations according to the prohibited lists announced by the World Antidoping Agency (WADA) are becoming of increasing interest to forensic chemists. In this review, the theoretical principles of optical biosensors based on noble metal nanoparticles, and the transduction mechanism of commonly-applied plasmonic biosensors are covered. We review different classes of recently-developed plasmonic biosensors for analytic determination...
Green chemistry and coronavirus
, Article Sustainable Chemistry and Pharmacy ; Volume 21 , 2021 ; 23525541 (ISSN) ; Rabiee, N ; Fatahi, Y ; Hooshmand, S. E ; Bagherzadeh, M ; Rabiee, M ; Jajarmi, V ; Dinarvand, R ; Habibzadeh, S ; Saeb, M. R ; Varma, R. S ; Shokouhimehr, M ; Hamblin, M. R ; Sharif University of Technology
Elsevier B.V
2021
Abstract
The novel coronavirus pandemic has rapidly spread around the world since December 2019. Various techniques have been applied in identification of SARS-CoV-2 or COVID-19 infection including computed tomography imaging, whole genome sequencing, and molecular methods such as reverse transcription polymerase chain reaction (RT-PCR). This review article discusses the diagnostic methods currently being deployed for the SARS-CoV-2 identification including optical biosensors and point-of-care diagnostics that are on the horizon. These innovative technologies may provide a more accurate, sensitive and rapid diagnosis of SARS-CoV-2 to manage the present novel coronavirus outbreak, and could be...
Green chemistry and coronavirus
, Article Sustainable Chemistry and Pharmacy ; Volume 21 , 2021 ; 23525541 (ISSN) ; Rabiee, N ; Fatahi, Y ; Hooshmand, S. E ; Bagherzadeh, M ; Rabiee, M ; Jajarmi, V ; Dinarvand, R ; Habibzadeh, S ; Saeb, M. R ; Varma, R.S ; Shokouhimehr, M ; Hamblin, M. R ; Sharif University of Technology
Elsevier B.V
2021
Abstract
The novel coronavirus pandemic has rapidly spread around the world since December 2019. Various techniques have been applied in identification of SARS-CoV-2 or COVID-19 infection including computed tomography imaging, whole genome sequencing, and molecular methods such as reverse transcription polymerase chain reaction (RT-PCR). This review article discusses the diagnostic methods currently being deployed for the SARS-CoV-2 identification including optical biosensors and point-of-care diagnostics that are on the horizon. These innovative technologies may provide a more accurate, sensitive and rapid diagnosis of SARS-CoV-2 to manage the present novel coronavirus outbreak, and could be...