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Synthesis and Study of Electron Transport through a Self-Assembled Monolayer of Thiol-End-Functionalized Tetraphenylporphyrines and Metalo-Tetraphenylporphyrines and Electrochemical Analysis of Dopamine and Ascorbic Acid with this SAMs
, M.Sc. Thesis Sharif University of Technology ; Mohammadi Boghaei, Davar (Supervisor)
Abstract
Self-Assembled Monolayer (SAM) is the first step in all surface engineering and assembly processes. It is used in sensor fabrication, memories and molecular recognition and optoelectronic devises as an active surface for patterning and chemical architecting of solid substrates. Tetraphenyl porphyrins because of their high stability and uniqe electronic and optic properties, that comes from their conjugate π electrons, easily can be used in these monolayers. Moreover they have a wide application because of their ability for coordination with metals and accepting substituents with electron donating and withdrawing properties. Electron transport through these layars which attach to the surface...
High-performance enzyme-free glucose sensor with Co-Cu nanorod arrays on Si substrates
, Article Recent Patents on Biotechnology ; Volume 12, Issue 2 , 2018 , Pages 126-133 ; 18722083 (ISSN) ; Yazdanpanah, A ; Karponis, D ; Aghabarari, B ; Tahmasbi, M ; Seifalian, A ; Mozafari, M ; Sharif University of Technology
Bentham Science Publishers B.V
2018
Abstract
Background: Glucose sensors have been extensively researched in patent studies and manufactured a tool for clinical diabetes diagnosis. Although some kinds of electrochemical enzymatic glucose sensors have been commercially successful, there is still room for improvement, in selectivity and reliability of these sensors. Because of the intrinsic disadvantages of enzymes, such as high fabrication cost and poor stability, non-enzymatic glucose sensors have recently been promoted as next generation diagnostic tool due to their relatively low cost, high stability, prompt response, and accuracy. Objective: In this research, a novel free standing and binder free non-enzymatic electrochemical sensor...
Cycling performance of LiFePO4/graphite batteries and their degradation mechanism analysis via electrochemical and microscopic techniques
, Article Ionics ; 2021 ; 09477047 (ISSN) ; Mosallanejad, B ; Mohammadzad, M ; Hosseini Hosseinabad, S. M ; Ramakrishna, S ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
In this work, cycling-induced aging occurring in 18650-type LiFePO4/graphite full cells at different C-rates is studied extensively. The mechanism of performance degradation is investigated using a combination of electrochemical and microstructural analyses. Half-cell studies are carried out after dismantling the full cells, using fresh and cycled LiFePO4 cathode and graphite anode to independently study them. The results show that the capacity of LiFePO4 electrodes is significantly recovered. The rate of capacity fading in the discharge state considered as irreversible capacity in the graphite is higher than LiFePO4 half cells, indicating a greater degradation in the performance of this...
Cycling performance of LiFePO4/graphite batteries and their degradation mechanism analysis via electrochemical and microscopic techniques
, Article Ionics ; Volume 28, Issue 1 , 2022 , Pages 213-228 ; 09477047 (ISSN) ; Mosallanejad, B ; Mohammadzad, M ; Hosseini Hosseinabad, S. M ; Ramakrishna, S ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
In this work, cycling-induced aging occurring in 18650-type LiFePO4/graphite full cells at different C-rates is studied extensively. The mechanism of performance degradation is investigated using a combination of electrochemical and microstructural analyses. Half-cell studies are carried out after dismantling the full cells, using fresh and cycled LiFePO4 cathode and graphite anode to independently study them. The results show that the capacity of LiFePO4 electrodes is significantly recovered. The rate of capacity fading in the discharge state considered as irreversible capacity in the graphite is higher than LiFePO4 half cells, indicating a greater degradation in the performance of this...
An ultrasensitive label free human papilloma virus DNA biosensor using gold nanotubes based on nanoporous polycarbonate in electrical alignment
, Article Analytica Chimica Acta ; Volume 1048 , 2019 , Pages 31-41 ; 00032670 (ISSN) ; Ghorbani, M ; Sasanpour, P ; Karimizefreh, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
An impedimetric human papilloma virus (HPV) DNA biosensor based on gold nanotubes (AuNTs) in label free detection was materialized. The AuNTs decorated nanoporous polycarbonate (AuNTs-PC) template as biosensor electrode was fabricated by electrodeposition method. The single strand DNA (ss-DNA) probe was covalently immobilized onto the AuNTs-PC electrode. The hybridization of target sequences with the ss-DNA probe was observed by the electrochemical impedance spectroscopy (EIS). The biosensor showed high selectivity and could differentiate between the complementary, mismatch and non-complementary DNA sequences. The EIS measurements were matched to Randle's equivalent circuit. The...
Mesoporous nanostructures of NiCo-LDH/ZnCo2O4 as an efficient electrocatalyst for oxygen evolution reaction
, Article Journal of Colloid and Interface Science ; Volume 604 , 2021 , Pages 832-843 ; 00219797 (ISSN) ; Shahrokhian, S ; Amini, M. K ; Sharif University of Technology
Academic Press Inc
2021
Abstract
Increasing energy demands for pollution-free and renewable energy technologies have stimulated intense research on the development of inexpensive, highly efficient, and stable non-noble metal electrocatalysts for oxygen evolution reaction (OER). In this study, a superior OER performance was achieved using a tri-metallic (Zn, Co, Ni) high-performance electrocatalyst. We successfully fabricated a peony-flower-like hierarchical ZnCo2O4 through an additive-free hydrothermal reaction followed by heat treatment. Then NiCo-LDH (layered double hydroxides) nano-flakes was electrodeposited on the ZnCo2O4/GCE surface to prepare NiCo-LDH/ZnCo2O4/GCE which was used as electrode for OER. The structure and...
Pd-Au nanoparticle decorated carbon nanotube as a sensing layer on the surface of glassy carbon electrode for electrochemical determination of ceftazidime
, Article Materials Science and Engineering C ; Vol. 34, issue. 1 , 2014 , pp. 318-325 ; ISSN: 09284931 ; Salimian, R ; Rastgar, S ; Sharif University of Technology
Abstract
A simple electrodeposition method is employed to construct a thin film modifier of palladium-gold nanoparticles (Pd-AuNPs) decorated multi-walled carbon nanotube (MWCNT) on the surface of glassy carbon electrode (GCE). Morphology and property of Pd-AuNPs-MWCNT have been examined by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Electrochemical performance of Pd-AuNPs-MWCNT/GCE for detection of ceftazidime (CFZ) has been investigated by cyclic voltammetry (CV). This nanostructured film modified electrode effectively exhibited enhanced properties for detection of ceftazidime (CFZ). The effects of various experimental variables such as, the amount of casted MWCNT,...
Electrochemical determination of clozapine on MWCNTs/new coccine doped ppy modified GCE: An experimental design approach
, Article Bioelectrochemistry ; Volume 90 , 2013 , Pages 36-43 ; 15675394 (ISSN) ; Kamalzadeh, Z ; Hamzehloei, A ; Sharif University of Technology
2013
Abstract
The electrooxidation of clozapine (CLZ) was studied on the surface of a glassy carbon electrode (GCE) modified with a thin film of multiwalled carbon nanotubes (MWCNTs)/new coccine (NC) doped polypyrrole (PPY) by using linear sweep voltammetry (LSV). The pH of the supporting electrolyte (D), drop size of the cast MWCNTs suspension (E) and accumulation time of CLZ on the surface of modified electrode (F) was considered as effective experimental factors and the oxidation peak current of CLZ was selected as the response. By using factorial-based response-surface methodology, the optimum values of factors were obtained as 5.44, 10 μL and 300 s for D, E and F respectively. Under the optimized...
Modification of glassy carbon electrode with a bilayer of multiwalled carbon nanotube/tiron-doped polypyrrole: Application to sensitive voltammetric determination of acyclovir
, Article Materials Science and Engineering C ; Volume 53 , 2015 , Pages 134-141 ; 09284931 (ISSN) ; Azimzadeh, M ; Amini, M. K ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
A novel voltammetric sensor based on glassy carbon electrode (GCE) modified with a thin film of multi-walled carbon nanotubes (MWCNTs) coated with an electropolymerized layer of tiron-doped polypyrrole was developed and the resulting electrode was applied for the determination of acyclovir (ACV). The surface morphology and property of the modified electrode were characterized by field emission scanning electron microscopy and electrochemical impedance spectroscopy techniques. The electrochemical performance of the modified electrode was investigated by means of linear sweep voltammetry (LSV). The effect of several experimental variables, such as pH of the supporting electrolyte, drop size of...
Voltammetric behavior and determination of trace amounts of omeprazole using an edge-plane pyrolytic graphite electrode
, Article Iranian Journal of Pharmaceutical Research ; Volume 14, Issue 2 , Spring , 2015 , Pages 465-471 ; 17350328 (ISSN) ; Ghalkhani, M ; Bayat, M ; Ghorbani Bidkorbeh, F ; Sharif University of Technology
Iranian Journal of Pharmaceutical Research
2015
Abstract
The voltammetric performance of edge-plane pyrolytic graphite (EPG) electrode via adsorptive stripping voltammetry was investigated for study of the electrochemical behavior of omeprazole (OMZ) in aqueous solution. The results revealed that the oxidation of OMZ is an irreversible pH-dependent process that proceeds with the transfer of one electron and one proton in an adsorption-controlled mechanism. The determination conditions, such as the pH values of the supporting electrolyte, accumulation time and scan rate were optimized. Simplicity, high reproducibility and low detection limit (3 nM) of the electrode response as well as wide linear range (0.01 to 4.0 µM) can be stated as significant...
Direct growth of metal-organic frameworks thin film arrays on glassy carbon electrode based on rapid conversion step mediated by copper clusters and hydroxide nanotubes for fabrication of a high performance non-enzymatic glucose sensing platform
, Article Biosensors and Bioelectronics ; Volume 112 , 2018 , Pages 100-107 ; 09565663 (ISSN) ; Khaki Sanati, E ; Hosseini, H ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The direct growth of self-supported metal-organic frameworks (MOFs) thin film can be considered as an effective strategy for fabrication of the advanced modified electrodes in sensors and biosensor applications. However, most of the fabricated MOFs-based sensors suffer from some drawbacks such as time consuming for synthesis of MOF and electrode making, need of a binder or an additive layer, need of expensive equipment and use of hazardous solvents. Here, a novel free-standing MOFs-based modified electrode was fabricated by the rapid direct growth of MOFs on the surface of the glassy carbon electrode (GCE). In this method, direct growth of MOFs was occurred by the formation of vertically...
Fabrication of a sensitive and fast response electrochemical glucose sensing platform based on co-based metal-organic frameworks obtained from rapid in situ conversion of electrodeposited cobalt hydroxide intermediates
, Article Talanta ; Volume 210 , 2020 ; Ezzati, M ; Hosseini, H ; Sharif University of Technology
Elsevier B.V
2020
Abstract
In this study, for the first time, we reported a fast and facile three-step in situ strategy for direct controllable growth of the Co3(BTC)2 MOFs thin films on the GCE, through the rapid conversion of the electrodeposited Co(OH)2 nano-flakes on rGO/GCE, to crystalline rectangular bar-shape structures of MOFs. X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy and elemental mapping analysis used to the structural and morphological characterization of the well-synthesized MOFs. The as-prepared Co3(BTC)2 MOFs were used to construct a non-enzymatic sensing platform for determining the glucose...
Hybrid supercapacitors constructed from double-shelled cobalt-zinc sulfide/copper oxide nanoarrays and ferrous sulfide/graphene oxide nanostructures
, Article Journal of Colloid and Interface Science ; Volume 585 , 2021 , Pages 750-763 ; 00219797 (ISSN) ; Hekmat, F ; Shahrokhian, S ; Sharif University of Technology
Academic Press Inc
2021
Abstract
Evolution of renewable energies in the era of the modernized world has been strongly tied up to the incessant development of high-performance energy storage systems benefiting from both high energy and power densities. In the present work, binder-free positive electrodes are fabricated via a facile electrochemical deposition route in which copper oxide nanorods (CuO NRs) directly grown onto the copper foam (CF) are decorated with bimetallic cobalt-zinc sulfide nanoarrays (Co-Zn-S NAs). The fabricated Co-Zn-S@CuO-CFs represent promising specific capacity of 317.03 C.g−1 at 1.76 A.g−1, along with superior cyclic stability (113% retention after 4500 cycles). Negative electrodes were further...
ZnO nanoparticle/nanorod-based label-free electrochemical immunoassay for rapid detection of MMP-9 biomarker
, Article Biochemical Engineering Journal ; Volume 164 , 2020 ; Abdekhodaie, M. J ; Mousavi, S. A ; Taghipour, F ; Sharif University of Technology
Elsevier B.V
2020
Abstract
A label-free electrochemical biosensor was developed for the rapid detection of the matrix metalloproteinase 9 (MMP-9) biomarker on the basis of antibody immobilizing on the zinc oxide (ZnO) nanoparticle and ZnO nanorod electrodes. The charge transfer resistance (Rct) of the electrodes was used as the indicator for MMP-9 concentration, which was obtained through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The ZnO nanorod-based biosensor exhibited linear behavior in the MMP-9 concentration range of 1–1000 ng/ml, which is a wider range than the available concentration ranges for most of the conventional methods. The biosensor sensitivity was 32.5 μA/(decade × cm2)...
Laboratory detection methods for the human coronaviruses
, Article European Journal of Clinical Microbiology and Infectious Diseases ; Volume 40, Issue 2 , 2021 , Pages 225-246 ; 09349723 (ISSN) ; Dowlatshahi, S ; Abdekhodaie, M. J ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
Coronaviruses are a group of envelop viruses which lead to diseases in birds and mammals as well as human. Seven coronaviruses have been discovered in humans that can cause mild to lethal respiratory tract infections. HCoV-229E, HCoV-OC43, HCoV-NL63, and HCoV-HKU1 are the low-risk members of this family and the reason for some common colds. Besides, SARS-CoV, MERS-CoV, and newly identified SARS-CoV-2, which is also known as 2019-nCoV, are the more dangerous viruses. Due to the rapid spread of this novel coronavirus and its related disease, COVID-19, a reliable, simple, fast, and low-cost detection method is necessary for patient diagnosis and tracking worldwide. Human coronaviruses detection...
Synthesis and characterization of new triphenylamine-based dyes with novel anchoring groups for dye-sensitized solar cell applications
, Article Journal of Materials Science: Materials in Electronics ; Volume 28, Issue 2 , 2017 , Pages 1859-1868 ; 09574522 (ISSN) ; Hosseinzadeh, B ; Azari, M ; Ghahary, R ; Sharif University of Technology
Springer New York LLC
2017
Abstract
Three new chromophores based on the triphenylamine (MM, DM, DN) with various novel electron withdrawing anchoring groups have been synthesized for use in dye-sensitized solar cells (DSSCs). The sensitizers were characterized by 1H and 13C NMR, Mass, UV–Vis, and electrochemical analysis. The HOMO and LUMO electron distributions of the sensitizers were calculated using density functional theory on a B3LYP level for geometry optimization. The DSSC device based on DM dye showed the best photovoltaic performance among MM and DN dyes: maximum monochromatic incident photon-to-current conversion efficiency (IPCE) of 98 %, short circuit current (JSC) of 4.58 mA/cm2, open circuit voltage (VOC) of...
Enhanced electrochemical activity of a hollow carbon sphere/polyaniline-based electrochemical biosensor for HBV DNA marker detection
, Article ACS Biomaterials Science and Engineering ; Volume 5, Issue 5 , 2019 , Pages 2587-2594 ; 23739878 (ISSN) ; Shahrokhian, S ; Panahi, S ; Sharif University of Technology
American Chemical Society
2019
Abstract
Herein, we present a novel, simple, and ultrasensitive electrochemical DNA (E-DNA) sensor based on hollow carbon spheres (HCS) decorated with polyaniline (PANI). A thiolated 21-mer oligonucleotide, characteristic of HBV DNA, is immobilized via electrodeposited gold nanoparticles on HCS-PANI. Cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) are used to characterize the electrochemical properties of the prepared nanocomposite. Scanning electron microscopy is employed to investigate the morphological texture of the fabricated modifier. An enhanced intrinsic signal of PANI is probed to evaluate the biosensing ability of the prepared...
Multilayered mesoporous composite nanostructures for highly sensitive label-free quantification of cardiac troponin-i
, Article Biosensors ; Volume 12, Issue 5 , 2022 ; 20796374 (ISSN) ; Amidian, M. A ; Sheybanikashani, S ; Mahdavi, H ; Alimohammadi, H ; Syedmoradi, L ; Mohandes, F ; Zarrabi, A ; Tamjid, E ; Omidfar, K ; Simchi, A ; Sharif University of Technology
MDPI
2022
Abstract
Cardiac troponin-I (cTnI) is a well-known biomarker for the diagnosis and control of acute myocardial infarction in clinical practice. To improve the accuracy and reliability of cTnI electrochemical immunosensors, we propose a multilayer nanostructure consisting of Fe3O4-COOH labeled anti-cTnI monoclonal antibody (Fe3O4-COOH-Ab1 ) and anti-cTnI polyclonal antibody (Ab2 ) conjugated on Au-Ag nanoparticles (NPs) decorated on a metal–organic framework (Au-Ag@ZIF-67-Ab2 ). In this design, Fe3O4-COOH was used for separation of cTnI in specimens and signal amplification, hierarchical porous ZIF-67 extremely enhanced the specific surface area, and Au-Ag NPs synergically promoted the conductivity...
Highly sensitive voltammetric determination of lamotrigine at highly oriented pyrolytic graphite electrode
, Article Bioelectrochemistry ; Volume 84 , 2012 , Pages 38-43 ; 15675394 (ISSN) ; Shahrokhian, S ; Sharif University of Technology
2012
Abstract
The electrochemical behavior of lamotrigine (LMT) at the pyrolytic graphite electrode (PGE) is investigated in detail by the means of cyclic voltammetry. During the electrochemical reduction of LMT, an irreversible cathodic peak appeared. Cyclic voltammetric studies indicated that the reduction process has an irreversible and adsorption-like behavior. The observed reduction peak is attributed to a two-electron process referring to the reduction of azo group. The electrode showed an excellent electrochemical activity toward the electro-reduction of LMT, leading to a significant improvement in sensitivity as compared to the glassy carbon electrode. The results of electrochemical impedance...
A study on the effects of Fex/Niy/MgO(1-x-y) catalysts on the volumetric and electrochemical hydrogen storage of multi-walled carbon nanotubes
, Article International Journal of Hydrogen Energy ; Volume 35, Issue 1 , 2010 , Pages 231-237 ; 03603199 (ISSN) ; Mortazavi, S. Z ; Zaker Moshfegh, A ; Nozad Golikand, A ; Sharif University of Technology
Abstract
The effects of various ratios of Fe/Ni/MgO and growth temperatures on yield, diameter and quality of multi-walled carbon nanotubes (MWCNTs) were studied. Thermal gravimetric analysis (TGA) confirmed that the MWCNT yield depends on Fe/Ni ratio with the following order; Fe0.5 Ni0.5 > Fe > Fe0.75 Ni0.25 > Fe0.25 Ni0.75 > Ni. The results indicated that there is an optimum temperature (940 °C) for the MWCNT growth both from quality and quantity (yield) aspects as compared to other temperatures. Moreover, the changes on Fe/Ni to MgO ratio for the MWCNT growth revealed that Fe/Ni/MgO with the ratio of 17.5/17.5/65 had the highest quality and surface area as compared to the other ratios. The...