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electrochemical-sensors
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Facile electrochemical detection of morpholine in boiler water with carbon nanostructures: a comparative study of graphene and carbon nanotubes
, Article Bulletin of Materials Science ; Volume 45, Issue 2 , 2022 ; 02504707 (ISSN) ; dos Santos Castro Assis, K. L ; Paiva, V. M ; Hashempour, M ; Bestetti, M ; de Araújo, J. R ; D’Elia, E ; Sharif University of Technology
Springer
2022
Abstract
Two electrochemical sensors based on modified glassy carbon electrodes with carbon nanostructures as graphene (GCE–EG) and carbon nanotubes (GCE–CNT) were evaluated for morpholine analysis. The carbon nanostructures were obtained and characterized using X-ray photoelectron spectroscopy, Raman spectroscopy, X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy and cyclic voltammetry. All spectroscopic and microscopic techniques confirmed the procurement of graphene and CNT. The electrochemical studies proved the efficient behaviour of both electrodes GCE–EG and GCE–CNT in sensing and detection of morpholine via differential pulse voltammetry....
Development of an electrochemical sensor based on (rGO-CNT) nanocomposite for raloxifene analysis
, Article Materials Chemistry and Physics ; Volume 263 , 2021 ; 02540584 (ISSN) ; Shahrokhian, S ; Navabi, M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
A novel modified electrode is reported for the electrochemical investigation of the oxidation mechanism and also voltammetric determination of raloxifene (RLX). The surface of the electrode was modified with a thin layer of reduced graphene oxide-carbon nanotube nano-composite (rGO-CNT) was prepared, and successfully employed for the electrochemical studies of RLX. The morphology of the sensor surface was characterized by using a scanning electron microscopy. RLX Oxidation response significantly increased at the GCE covered with rGO-CNT, regarding the bare and CNT or rGO functionalized GCE. Experimental parameters affecting the RLX response were optimized and mechanism of the RLX oxidation...
Bimetallic CoZn-MOFs easily derived from CoZn-LDHs, as a suitable platform in fabrication of a non-enzymatic electrochemical sensor for detecting glucose in human fluids
, Article Sensors and Actuators B: Chemical ; Volume 344 , 2021 ; 09254005 (ISSN) ; Shahrokhian, S ; Ezzati, M ; Sharif University of Technology
Elsevier B.V
2021
Abstract
In the present study, an in-situ, two-step, highly controllable, fast, green, and facile strategy for fabricating the bimetallic cobalt-zinc-based metal-organic frameworks (MOFs) is employed for designing a non-enzymatic glucose sensing platform. The structural characterization, as well as the phase investigation of materials in each step, are assessed by X-ray diffraction, energy-dispersive X-ray spectroscopy, elemental mapping, field emission scanning electron microscopy, and Fourier transform infrared spectroscopy. Furthermore, the electrocatalytic activity of the CoZn-BTC/GC fabricated electrode toward the electro-oxidation of glucose is examined by various electrochemical techniques,...
Review - Towards the two-dimensional hexagonal boron nitride (2D h-BN) electrochemical sensing platforms
, Article Journal of the Electrochemical Society ; Volume 167, Issue 12 , 2020 ; Khalaj, M ; Alem, S. A. A ; Pakdel, A ; Willander, M ; Hatamie, A ; Simchi, A ; Sharif University of Technology
IOP Publishing Ltd
2020
Abstract
Electrochemical sensing performance of two-dimensional hexagonal boron nitride (2D h-BN) has traditionally been suppressed by their intrinsic electrical insulation and deficient electron transportation mechanism. However, the excellent electrocatalytic activity, high specific surface area, N- and B-active edges, structural defects, adjustable band gap through interaction with other nanomaterials, and chemical functionalization, makes 2D h-BN ideal for many sensing applications. Therefore, finding a pathway to modulate the electronic properties of 2D h-BN while the intrinsic characteristics are well preserved, will evolve a new generation of highly sensitive and selective electrochemical...
Microfluidic devices with gold thin film channels for chemical and biomedical applications: a review
, Article Biomedical Microdevices ; Volume 21, Issue 4 , 2019 ; 13872176 (ISSN) ; Rabiee, N ; Rabiee, M ; Bagherzadeh, M ; Tahriri, M ; Tayebi, L ; Hamblin, M. R ; Sharif University of Technology
Springer New York LLC
2019
Abstract
Microfluidic systems (MFS) provide a range of advantages in biomedical applications, including improved controllability of material characteristics and lower consumption of reagents, energy, time and money. Fabrication of MFS employs various materials, such as glass, silicon, ceramics, paper, and metals such as gold, copper, aluminum, chromium and titanium. In this review, gold thin film microfluidic channels (GTFMFC) are discussed with reference to fabrication methods and their diverse use in chemical and biomedical applications. The advantages of gold thin films (GTF) include flexibility, ease of manufacture, adhesion to polymer surfaces, chemical stability, good electrical conductivity,...
Numerical simulation of a microfluidic system for regular glucose measurement
, Article 26th National and 4th International Iranian Conference on Biomedical Engineering, ICBME 2019, 27 November 2019 through 28 November 2019 ; 2019 , Pages 60-65 ; 9781728156637 (ISBN) ; Saidi, M. S ; Shahrokhian, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
The aim of this research is to design an implantable integrated microfluidic system in order to regularly measure the glucose level in the human body, nonenzymatically, using the microdialysis method. The main compartments of this system are a micropump, array of hollow microneedles and an electrochemical sensor. At the base of the microneedles, there are located semipermeable membranes, that when the pumped dialysis fluid passes over them, the glucose of the interstitial fluid diffuses into the dialysis fluid and then, in the sensor section, it is measured nonenzymatically using the amperometry method. Both the arrangement of the miconeedles and the amount of the dialysis fluid flow are...
Electrochemical sensing based on carbon nanoparticles: A review
, Article Sensors and Actuators, B: Chemical ; Volume 293 , 2019 , Pages 183-209 ; 09254005 (ISSN) ; Ghalkhani, M ; Shahrokhian, S ; Sharif University of Technology
Elsevier B.V
2019
Abstract
The emergence of nanoscience and nanotechnology has opened up new horizons to researchers. In this regard, carbon nanomaterials are considered as the cornerstone of numerous investigations. Among various carbon nanostructures, “Carbon nanoparticles (CNPs)” have attracted a great deal of attention during the past few years due to their unique properties such as high surface area, non-toxicity, biocompatibility as well as simple and low-cost synthetic procedures via environmentally friendly routes. Thanks to these properties along with their interesting optical behavior, CNPs have found diverse applications in the fields of bioimaging, nanomedicine, photo/electro-catalysis, and bio/chemical...
Advanced on-site glucose sensing platform based on a new architecture of free-standing hollow Cu(OH)2 nanotubes decorated with CoNi-LDH nanosheets on graphite screen-printed electrode
, Article Nanoscale ; Volume 11, Issue 26 , 2019 , Pages 12655-12671 ; 20403364 (ISSN) ; Khaki Sanati, E ; Hosseini, H ; Sharif University of Technology
Royal Society of Chemistry
2019
Abstract
The planned design of nanocomposites combined with manageable production processes, which can offer controllability over the nanomaterial structure, promises the practical applications of functional nanomaterials. Hollow core-shell nanostructure architectures represent an emerging category of advanced functional nanomaterials, whose benefits derived from their notable properties may be hampered by complicated construction processes, especially in the sensing domain. In this regard, we designed a highly porous three-dimensional array of hierarchical hetero Cu(OH)2@CoNi-LDH core-shell nanotubes via a quick, very simple, green, and highly controllable three-step in situ method; they were...
Ni(II) 1D-coordination polymer/C 60 -modified glassy carbon electrode as a highly sensitive non-enzymatic glucose electrochemical sensor
, Article Applied Surface Science ; Volume 478 , 2019 , Pages 361-372 ; 01694332 (ISSN) ; Mohammadi, R ; Ghanbari, B ; Shahrokhian, S ; Sharif University of Technology
Elsevier B.V
2019
Abstract
A new non-enzymatic sensor for glucose is prepared by using of Ni(II)-one dimensional coordination polymer (Ni(II)-Cp) and C 60 . The Ni(II)-Cp prepared by slow diffusion and evaporation of two solution layers of NiCl 2 and diaza-macrocycle bearing two pyridine side arms (as the reported tecton) in DMF. The Ni(II)-Cp was characterized by powder x-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) as well as Fourier transform infrared spectroscopy (FT-IR). C 60 as modified was added to Ni(II)-Cp for improving the electrical and chemical stability of the composite. The newly assembled Ni(II)-Cp/C 60 also coated on glassy carbon electrode (GC) to...
Yttrium hexacyanoferrate microflowers on freestanding three-dimensional graphene substrates for ascorbic acid detection
, Article ACS Applied Nano Materials ; Volume 2, Issue 4 , 2019 , Pages 2212-2221 ; 25740970 (ISSN) ; Rahmati, R ; Rezvani, E ; Angizi, S ; Simchi, A ; Sharif University of Technology
American Chemical Society
2019
Abstract
Recently, three-dimensional carbon nanostructures have attracted significant attention for biosensing applications. We have prepared highly porous three-dimensional graphene (3DG) structures (90% porosity) by template-assisted chemical vapor deposition technique and enhanced their electrocatalytic activity through in situ electrochemical deposition of rose-like yttrium hexacyanoferrate particles on their struts. The 3DG structure has an average channel size of ∼500 μm, and the microflowers have lateral sizes in the range of 2-10 μm. The performance of the 3DG-based electrode in efficient detection of ascorbic acid was investigated after transferring on a gold screen printed electrode (SPE)....
Fast and ultra-sensitive voltammetric detection of lead ions by two-dimensional graphitic carbon nitride (g-C3N4) nanolayers as glassy carbon electrode modifier
, Article Measurement: Journal of the International Measurement Confederation ; Volume 134 , 2019 , Pages 679-687 ; 02632241 (ISSN) ; Jalilian, P ; Rezvani, E ; Kakavand, A ; Simchi, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Recently, graphitic carbon nitride (g-C3N4) has attracted great interest for photo(electro)chemical applications such as sensing, solar energy exploitation, photocatalysis, and hydrogen generation. This paper presents the potential application and benefits of g-C3N4 nanolayers as a green and highly efficient electrode modifier for the detection of trace lead ions in drinking water and urban dust samples. Carbon nitride nanosheets with a thickness of ∼6 A° and lateral of 100–150 nm were prepared through high-temperature polymerization of melamine followed by sonication-assisted liquid exfoliation. A glassy carbon electrode (GCE) was modified by a thin layer of g-C3N4 through drop casting and...
Electrochemical sensors based on functionalized carbon nanotubes modified with platinum nanoparticles for the detection of sulfide ions in aqueous media
, Article Journal of Chemical Sciences ; Volume 131, Issue 3 , 2019 ; 09743626 (ISSN) ; Dolati, A ; Salmani Rezaie , S ; Sharif University of Technology
Springer
2019
Abstract
Abstract : Vertically aligned carbon nanotube (CNT) arrays were synthesized by thermal chemical vapor deposition (CVD) on stainless steel substrates coated by cobalt nanoparticles as catalyst. Morphological and elemental analyses conducted by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) revealed that bamboo-like CNTs were blocked by Co nanoparticles at the tips. The fabricated nanotubes underwent functionalization by electrochemical oxidation in sulfuric acid, and the subsequent structural studies, as well as Fourier transform infrared (FTIR) spectroscopy confirmed that the tips of functionalized CNTs were opened while oxygenated functional groups were...
Electrochemical preparation of a molecularly imprinted polypyrrole modified pencil graphite electrode for the determination of phenothiazine in model and real biological samples
, Article Talanta ; Volume 144 , November , 2015 , Pages 456-465 ; 00399140 (ISSN) ; Rouki, Z ; Nezhadali, M ; Sharif University of Technology
Elsevier
2015
Abstract
Abstract A sensitive electrochemical sensor for determination of phenothiazine (PTZ) was introduced based on molecularly imprinted polymer (MIP) film. A computational study was performed to evaluate the template-monomer geometry and interaction energy in the prepolymerization mixture. The electrode was prepared during electropolymerization of pyrrole (Py) on a pencil graphite electrode (PGE) by cyclic voltammetry (CV) technique. The quantitative measurements were performed using differential pulse voltammetry (DPV) in Britton-Robinson (BR) buffer solutions using 60% (v/v) acetonitrile-water (ACN/H2 O) binary solvent. The effect of important parameters like pH, monomer...
Glassy carbon electrode modified with a bilayer of multi-walled carbon nanotube and polypyrrole doped with new coccine: Application to the sensitive electrochemical determination of Sumatriptan
, Article Electrochimica Acta ; Volume 56, Issue 27 , November , 2011 , Pages 10032-10038 ; 00134686 (ISSN) ; Kamalzadeh, Z ; Saberi, R. S ; Sharif University of Technology
2011
Abstract
A promising electrochemical sensor was developed based on a layer by layer process by electro-polymerization of pyrrole in the presence of new coccine (NC) as dopant anion on the surface of the multi-walled carbon nanotubes (MWCNTs) pre-coated glassy carbon electrode (GCE). The modified electrode was used as a new and sensitive electrochemical sensor for voltammetric determination of sumatriptan (SUM). The electrochemical behavior of SUM was investigated on the surface of the modified electrode using linear sweep voltammetry (LSV). The results showed a remarkable increase (∼12 times) in the anodic peak current of SUM in comparison to the bare GCE. The effect of experimental variables such...
A kinetic study on the electrodeposition of nickel nanostructure and its electrocatalytic activity for hydrogen evolution reaction
, Article Journal of Applied Electrochemistry ; Volume 40, Issue 11 , November , 2010 , Pages 1941-1947 ; 0021891X (ISSN) ; Dolati, A ; Sharif University of Technology
2010
Abstract
The electrodeposition of nickel was studied using electrochemical techniques in different electrolytes and various agents. The voltammetry analysis clearly showed that the electrodeposition of nickel was a diffusion-controlled process associated with a typical nucleation process. The current transients represented instantaneous nucleation with a typical three-dimensional (3D) growth mechanism. Scharifker's equations were derived for instantaneous and progressive nucleation of the 3D growth of the spherical centers under diffusion-controlled condition. The number of nucleation sites increased with the increment in overpotential and Ni 2+ concentration. Atomic force microscopy was used to...
A preliminary study of the electro-catalytic reduction of oxygen on Cu-Pd alloys in alkaline solution
, Article Journal of Electroanalytical Chemistry ; Volume 647, Issue 1 , 2010 , Pages 66-73 ; 15726657 (ISSN) ; Arab, R ; Sharif University of Technology
2010
Abstract
Copper-palladium alloys of different compositions are electrodeposited on nickel from aqueous solutions. These alloys are characterized by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The catalytic activity of these alloys toward oxygen reduction reaction (ORR) in alkaline solution is investigated using rotating disk electrode (RDE). The number of electrons transferred per O2 molecule (n) obtained at different potentials is close to 2 at low overpotential indicating HO2- formation and gradually increases to 4 at higher overpotentials indicating full reduction to OH-. It is shown that Cu-Pd alloys are better electrocatalysts than Pd with Pd-Cu-1 having 24.5%...
Encapsulation of palladium nanoparticles by multiwall carbon nanotubes-graft-poly(citric acid) hybrid materials
, Article Journal of Applied Polymer Science ; Volume 116, Issue 4 , 2010 , Pages 2188-2196 ; 00218995 (ISSN) ; Mehdipour, E ; Bavadi, M ; Sharif University of Technology
2010
Abstract
Citric acid was polymerized onto the surface of functionalized multiwall carbon nanotubes (MWCNTCOOH) and MWCNT-graft-poly(citric acid) (MWCNTg-PCA) hybrid materials were obtained. Due to the grafted poly(citric acid) branches, MWCNT-g-PCA hybrid materials not only were soluble in water but also were able to trap water soluble metal ions. Reduction of trapped metal ions in the polymeric shell of MWCNT-g-PCA hybrid materials by reducing agents such as sodium borohydride led to encapsulated metal nanoparticles on the surface of MWCNT. Herein palladium nanoparticles were encapsulated and transported by MWCNT-g-PCA hybrid materials (MWCNT-g-PCA-EPN) and their application as nanocatalyst toward...
Selective voltammetric determination of d-penicillamine in the presence of tryptophan at a modified carbon paste electrode incorporating TiO2 nanoparticles and quinizarine
, Article Journal of Electroanalytical Chemistry ; Volume 644, Issue 1 , Jan , 2010 , Pages 1-6 ; 15726657 (ISSN) ; Beitollahi, H ; Taleat, Z ; Naeimi, H ; Taghavinia, N ; Sharif University of Technology
2010
Abstract
A carbon paste electrode (CPE) chemically modified with TiO2 nanoparticles and quinizarine (QZ) was used as a selective electrochemical sensor for the simultaneous determination of minor amounts of d-penicillamine (D-PA) and tryptophan (Trp). This modified electrode showed very efficient electrocatalytic activity for anodic oxidation of both d-PA and Trp. Substantial decreases of anodic overpotentials for both compounds made this analysis possible. Results of square wave voltammetry (SWV) using this modified electrode showed two well-resolved anodic waves for the oxidation of d-PA and Trp, which makes the simultaneous determination of both compounds possible. The peak potential for the...
Novel nanostructure electrochemical sensor for electrocatalytic determination of norepinephrine in the presence of high concentrations of acetaminophene and folic acid
, Article Applied Catalysis A: General ; Volume 378, Issue 2 , 2010 , Pages 195-201 ; 0926860X (ISSN) ; Beitollahi, H ; Sheikh Mohseni, M. A ; Naeimi, H ; Taghavinia, N ; Sharif University of Technology
2010
Abstract
In the present paper, the use of a carbon paste electrode modified by 2,2′-[1,2 buthanediylbis (nitriloethylidyne)]-bis-hydroquinone (BH) and TiO2 nanoparticles prepared by a simple and rapid method was described. The modified electrode showed an excellent character for electrocatalytic oxidization of norepinephrine (NE), acetaminophene (AC) and folic acid (FA). Using differential pulse voltammetry (DPV), a highly selective and simultaneous determination of NE, AC and FA has been explored at the modified electrode. Differential pulse voltammetry (DPV) peak currents of NE, AC and FA increased linearly with their concentration at the ranges of 4.0-1100.0 μM, 12.5-500.0 μM and 200.0-3200.0 μM,...
Differential pulse voltammetric determination of N-acetylcysteine by the electrocatalytic oxidation at the surface of carbon nanotube-paste electrode modified with cobalt salophen complexes
, Article Sensors and Actuators, B: Chemical ; Volume 133, Issue 2 , 12 August , 2008 , Pages 599-606 ; 09254005 (ISSN) ; Kamalzadeh, Z ; Bezaatpour, A ; Boghaei, D. M ; Sharif University of Technology
2008
Abstract
The preparation and electrochemical performance of the carbon nanotube-paste electrode modified with salophen complexes of cobalt(III) perchlorate, with various substituents on the salophen ligand, as well as their electrocatalytic activity toward the oxidation of N-acetylcysteine (NAC) is investigated. Several Schiff base complexes containing various nucleophilic and electrophilic functional groups were prepared, and their electrochemical characteristics for the electro-oxidation of NAC were evaluated using cyclic and differential pulse voltammetry (CV and DPV). The results revealed, the modified electrodes show an efficient and selective electrocatalytic activity toward the anodic...