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Determination of heavy metal ions by an amperometric biosensor based on glucose oxidase immobilized onto single-walled carbon nanotubes/Nile blue nanocomposite
, Article Journal of the Iranian Chemical Society ; Volume 15, Issue 8 , 2018 , Pages 1765-1774 ; 1735207X (ISSN) ; Sabzi, R. E ; Borghei, S. M ; Sharif University of Technology
Springer Verlag
2018
Abstract
An enzymatic electrochemical biosensor was prepared based on glucose oxidase (GOD) immobilized on single-walled carbon nanotubes/Nile blue (Nb–SWCNTs) nanocomposite cross-linked with glutaraldehyde on graphite electrode. The function of glucose biosensor is based on the electrocatalytic reduction of H2O2 generated by the reaction of the enzyme with glucose molecules. The biosensor was characterized by Fourier transform infrared (FTIR) spectroscopy, emission scanning (FESEM), UV–Vis spectrometry, and voltammetric and amperometric methods. Parameters influencing the performance of the biosensor, namely pH and applied potential, were optimized. Inhibition was carried out for the detection of...
Experimental Studies on the Application of Biosensors for Detection of Toxic Compounds
, M.Sc. Thesis Sharif University of Technology ; Roosta Azad, Reza (Supervisor) ; Kariminia, Hamid Reza (Supervisor)
Abstract
In this project, quantification of sulfide ion was investigated based on peroxidase enzyme inhibition. The fungal peroxidase was obtained from the liquid culture of Coprinus cinereus NBRC 30628. Two different biosensing systems were suggested for sulfide ion measurement: (1) An amperometric inhibition peroxidase biosensor proposed for determination of sulfide by in situ bulk polymerization of acrylamide for immobilization of peroxidase on screen-printed carbon electrode. Measurements were performed using phosphate buffer solution as a supporting electrolyte in the presence of hydroquinone as a mediator. Identification method was based on reduction of generation current, caused by hydrolysis...
Experimental Studies on the Application of Biosensor for Detection of Toxic Compound
, M.Sc. Thesis Sharif University of Technology ; Roosta Azad, Reza (Supervisor) ; Musavi, Abbas (Co-Advisor)
Abstract
In this research, an amperometric inhibition biosensor for the detection of cyanide has been fabricated by immobilization of the horseradish peroxidase (HRP) on the surface of glassy carbone electrode (GCE). Chitosan/acrylamide was applied for immobilization of HRP on the working electrode. All electrochemical measurement were carried out with three electrode: Ag/AgCl electrode as reference electrode, GCE as working electrode and platinium electrode as counter electrode which immersed in phosphate buffer solution. The amperometric measurement was done at an applied potential of -100 mV versus Ag/AgCl with a scan rate of 100 mV in the presence of hydroquinone as electron mediator and...
Two nanostructured polymers: Polyaniline nanofibers and new linear-dendritic matrix of poly(citric acid)-block-poly(ethylene glycol) copolymers for environmental monitoring in novel biosensors
, Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 62, Issue 7 , Jul , 2013 , Pages 377-383 ; 00914037 (ISSN) ; Vossoughi, M ; Alemzadeh, I ; Naeini, A. T ; Darvish, M ; Sharif University of Technology
2013
Abstract
In this work two phenol biosensors, one based on polyaniline nanofibers (PNFs) and the other based on the newly created and introduced linear-dendritic matrix of poly(citric acid)-block-poly(ethylene glycol) copolymers (PCA-PEG-PCA), were chemically modified with horseradish peroxidase (HRP) enzyme. These phenol biosensors showed an oxidation peak at 0.55 V. The amperometric response for biosensors based on PNFs showed a linear response range from 2.5 × 10-6 to 2.5 × 10-5 mol/L, with a detection limit of 2.5 M phenol. Also, the amperometric response for a biosensor based on PCA-PEG-PCA showed a linear response range from 2.5 × 10-6 to 4 × 10-5 mol/L, with a detection limit of 1.5 M phenol
Fabrication of Enzyme Biosensor for Heavy Metal Detection
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Sabzi, Reza (Supervisor)
Abstract
In this project identification of heavy metals has been studied by using glucose oxidase enzyme. Measurement of heavy metals such as mercury (II) nitrate, lead (II) nitrate and cadmium nitrate are based on inhibitory of glucose oxidase enzyme. To do this, two modified electrodes has stabilized on a graphite electrode. Nanocomposite of single wall carbon nanotube with Nile Blue is foundation of the first working electrode. Biological component of the electrode is glucose oxidase enzyme that bovine serum albumin and glutaraldehyde are helping enzyme in immobilization and these materials cause enzyme to cross link with the foundation. This biosensor has great stability and suitable linear...
Experimental Study on Biosensors for Detection of Biohazards with Nano-structured Metal Oxides Basis
, M.Sc. Thesis Sharif University of Technology ; Mashayekhan, Shohreh (Supervisor) ; Vosoughi, Manouchehr (Supervisor)
Abstract
In this research, fabrication of a mediator free nano-biosensor for the detection of cyanide has been studied. This biosensor utilizes 75 nm diameter (nano) ZnO particles synthesized with sol- gel method for modification and immobilization of Horseradish peroxidase (HRP). Cyanide plays inhibitory role in decomposition of H2O2 while HRP plays catalyst role in this reaction. Cyanide inhibits enzyme activity thorough binding with enzyme active sites and result in decreasing electrical current in electrochemical decomposition of H2O2. Amperometery response of biosensor shows linear relation between inhibition percent and cyanide concentration in range of 3µM - 24µM with detection limit of 0.62µM...
Electrodeposition and electrocatalytic properties of Pt/Ni-Co nanowires for non-enzymatic glucose detection
, Article Journal of Alloys and Compounds ; Volume 554 , 2013 , Pages 169-176 ; 09258388 (ISSN) ; Mahshid, S ; Dolati, A ; Ghorbani, M ; Yang, L ; Luo, S ; Cai, Q ; Sharif University of Technology
2013
Abstract
A nanowire arrays system consisting of an ordered configuration of Pt, Ni and Co was constructed in single-bath solution through pulse electrodeposition. This structure was evaluated as a potential amperometric non-enzymatic sensor to detect glucose in alkaline solution. We observed a strong and fast amperometric response at low applied potential of 0.4 V vs. SCE over linear ranges of 0-0.2 mM and 0.2-8 mM glucose with sensitivities of 1125 and 333 μA mM-1 cm-2, respectively. We also observed a low detection limit for glucose of 1 μM. Correlation of the electronic and geometric modifications with the electrochemical performance characteristics enhanced catalytic activity of the electrode by...
Amperometric sulfide detection using Coprinus cinereus peroxidase immobilized on screen printed electrode in an enzyme inhibition based biosensor
, Article Biosensors and Bioelectronics ; Volume 35, Issue 1 , 2012 , Pages 297-301 ; 09565663 (ISSN) ; Kariminia, H. R ; Ghadiri, M ; Roosta Azad, R ; Sharif University of Technology
2012
Abstract
In the present work, an amperometric inhibition biosensor for the determination of sulfide has been fabricated by immobilizing Coprinus cinereus peroxidase (CIP) on the surface of screen printed electrode (SPE). Chitosan/acrylamide was applied for immobilization of peroxidase on the working electrode. The amperometric measurement was performed at an applied potential of -150. mV versus Ag/AgCl with a scan rate of 100. mV in the presence of hydroquinone as electron mediator and 0.1. M phosphate buffer solution of pH 6.5. The variables influencing the performance of sensor including the amount of substrate, mediator concentration and electrolyte pH were optimized. The determination of sulfide...
Large scale inkjet-printing of carbon nanotubes electrodes for antioxidant assays in blood bags
, Article Journal of Electroanalytical Chemistry ; Vol. 717-718 , 2014 , Pages 61-68 ; ISSN: 15726657 ; Cortes Salazar, F ; Prudent, M ; Delobel, J ; Rastgar, S ; Lion, N ; Tissot J. D ; Tacchini, P ; Girault, H. H ; Sharif University of Technology
Abstract
Herein, we present the large scale fabrication of carbon nanotubes (CNT) electrodes supported on flexible polymeric sheets by subsequent multilayer inkjet printing of a silver layer for electrical connection, CNT layers as active electrode material and an insulation layer to define a stand-alone CNT active electrode area with high accuracy. Optical and electrochemical characterization using several redox mediators demonstrates the reproducibility of the electrode surfaces and their functionality even with a single inkjet printed CNT layer. These electrodes are targeted to the clinical sector for the determination of the antioxidant power (AOP) of biologically relevant fluids by...
Template-based electrodeposition of Pt/Ni nanowires and its catalytic activity towards glucose oxidation
, Article Electrochimica Acta ; Volume 58, Issue 1 , 2011 , Pages 551-555 ; 00134686 (ISSN) ; Mahshid, S ; Dolati, A ; Ghorbani, M ; Yang, L ; Luo, S ; Cai, Q ; Sharif University of Technology
2011
Abstract
An electro-catalysis non-enzymatic electrode is proposed based on alloyed Pt/Ni nanowire arrays (NWAs) for the detection of glucose. The Pt/Ni NWAs were prepared by pulse electrodeposition of Pt and Ni within a nano-pore polycarbonate (PC) membrane followed by a chemical etching of the membrane. The electrode structure is characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The resulting Pt/Ni NWAs electrode shows high electrocatalytic activities towards the oxidation of glucose in alkaline solution. Consequently, a sensitive amperometric detection of glucose is achieved under 0.45 V vs. SCE with a low detection limit of 1.5 μM within a wide linear...
A well-dispersed Pt/Ni/TiO 2 nanotubes modified electrode as an amperometric non-enzymatic glucose biosensor
, Article Sensor Letters ; Volume 9, Issue 5 , October , 2011 , Pages 1598-1605 ; 1546198X (ISSN) ; Luo, S ; Yang, L ; Mahshid, S ; Dolati, A ; Ghorbani, M ; Cai, Q ; Sharif University of Technology
2011
Abstract
In this study a novel Pt/Ni nanostructure consisting of nano-bushes and nanocubes was fabricated onto TiO 2 nanotubes. The scanning electron microscopy images showed that a large amount of well-dispersed nano-architectures had uniformly covered all over the surface which made an electrode with high surface area. It was obviously seen that the nanocube structures mainly consists of Ni had been grown on top of each other while the Pt colonies represented bush-like structures. As a non-enzymatic glucose biosensor, the Pt/Ni TiO 2 nanotubes modified electrode exhibited an excellent performance. The proposed biosensor had two linear ranges for detection of glucose from 0 to 0.12 mM (correlation...
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)....
Synthesis, first-principle simulation, and application of three-dimensional ceria nanoparticles/graphene nanocomposite for non-enzymatic hydrogen peroxide detection
, Article Journal of the Electrochemical Society ; Volume 166, Issue 5 , 2019 , Pages H3167-H3174 ; 00134651 (ISSN) ; Hatamie, A ; Berahman, M ; Simchi, M ; Angizi, S ; Rahmati, R ; Kennedy, J ; Simchi, A ; Sharif University of Technology
Electrochemical Society Inc
2019
Abstract
Owing to the exceptional properties of graphene and the crucial role of substrate on the performance of electrochemical biosensors, several graphene-based hybrid structures have recently emerged, yielding improved selectivity and sensitivity. To date, most of the reported biosensors utilize solution-driven graphene flakes with drawbacks of low conductivity (due to high inter-junction contact resistant) and structural fragility. Herein, we present a conductive three-dimensional CeO2 semiconductor nanoparticles/graphene nanocomposite, as a platform for sensitive detection of hydrogen peroxide, an important molecule in fundamental biological processes. The 3D conductive graphene architecture is...
Synthesis, first-principle simulation, and application of three-dimensional ceria nanoparticles/graphene nanocomposite for non-enzymatic hydrogen peroxide detection
, Article Journal of the Electrochemical Society ; Volume 166, Issue 5 , 2019 , Pages H3167-H3174 ; 00134651 (ISSN) ; Hatamie, A ; Berahman, M ; Simchi, M ; Angizi, S ; Rahmati, R ; Kennedy, J ; Simchi, A ; Sharif University of Technology
Electrochemical Society Inc
2019
Abstract
Owing to the exceptional properties of graphene and the crucial role of substrate on the performance of electrochemical biosensors, several graphene-based hybrid structures have recently emerged, yielding improved selectivity and sensitivity. To date, most of the reported biosensors utilize solution-driven graphene flakes with drawbacks of low conductivity (due to high inter-junction contact resistant) and structural fragility. Herein, we present a conductive three-dimensional CeO2 semiconductor nanoparticles/graphene nanocomposite, as a platform for sensitive detection of hydrogen peroxide, an important molecule in fundamental biological processes. The 3D conductive graphene architecture is...
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,...
Microwave-assisted decoration of cotton fabrics with Nickel-Cobalt sulfide as a wearable glucose sensing platform
, Article Journal of Electroanalytical Chemistry ; Volume 890 , 2021 ; 15726657 (ISSN) ; Ezzati, M ; Shahrokhian, S ; Unalan, H. E ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Flexibility and human-body compatibility have been emerged through the use of commercial fabrics (CFs) in designing wearable non-enzymatic glucose sensing platforms. In this work, electrodes fabricated through direct synthesis of ternary nickel–cobalt sulfide nanostructures (Ni-Co-S NSs) on the CFs (Ni-Co-S@CFs) using a fast and facile one-step microwave-assisted method for this purpose. Fabrication was followed by the structural and electrochemical characterization of the electrodes. The glucose-sensing ability of the prepared wearable electrodes was investigated via cyclic voltammetry (CV) and amperometry techniques in alkaline media. Two linear-responses in wide detection ranges of...
Direct decoration of carbon nanohorns with binary nickel-cobalt sulfide nanosheets towards non-enzymatic glucose sensing in human fluids
, Article Electrochimica Acta ; Volume 428 , 2022 ; 00134686 (ISSN) ; Hekmat, F ; Wang, H ; Amaratunga, G. A. J ; Unalan, H. E ; Shahrokhian, S ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
A highly controllable, green, and rapid strategy is demonstrated for fabricating of highly sensitive non-enzymatic glucose sensing platforms. Carbon nanohorns (CNHs) were decorated onto the screen-printed electrodes. Binary nickel-cobalt sulfide (NiCo-S) nanosheets (NSs) were then deposited on CNH-casted electrodes by a facile and scalable method. Following detailed structural characterization and the electrocatalytic activity of the fabricated NiCo-S/CNH electrodes towards electro-oxidation of glucose was examined in detail. The proposed electrodes operated within two distinct linear dynamic ranges of 0.001- 0.330 mM and 0.330 - 4.53 mM with sensitivities of 1842 µA.mM−1.cm−2 and 854...
Amine functionalized TiO2 coated on carbon nanotube as a nanomaterial for direct electrochemistry of glucose oxidase and glucose biosensing
, Article Journal of Molecular Catalysis B: Enzymatic ; Volume 68, Issue 2 , 2011 , Pages 206-210 ; 13811177 (ISSN) ; Rafiee Pour, H. A ; Ghourchian, H ; Gholami, M. R ; Sharif University of Technology
Abstract
A nano-composite material consisting of amine functionalized TiO 2-coated carbon nanotubes was prepared and used for glucose oxidase (GOx) absorption. The GOx bearing nanomaterial was fixed on a glassy carbon electrode to construct a novel biosensor for glucose determination. The direct electrochemistry of immobilized GOx and its electron transfer parameters at the modified glassy carbon electrode were reported. The apparent heterogeneous electron transfer rate constant (ks) of GOx was estimated to be 3.5 s-1, which is higher than those reported previously. Amperometric detection of glucose resulted in a rapid (3 s) and stable response in the linear concentration range from 1.8 to 266 μM....
Novel microfluidic graphene oxide–protein amperometric biosensor for detecting sulfur compounds
, Article Biotechnology and Applied Biochemistry ; Volume 66, Issue 3 , 2019 , Pages 353-360 ; 08854513 (ISSN) ; Abdi, K ; Javadi, S ; Shehneh, M. Z ; Yazdian, F ; Omidi, M ; Rashedi, H ; Haghiralsadat, B. F ; Asayeshnaeini, O ; Sharif University of Technology
Wiley-Blackwell Publishing Ltd
2019
Abstract
Sulfur compounds are essential for many industries and organisms; however, they cause serious respiratory problems in human beings. Therefore, determination of sulfur concentration is of paramount importance. The research approach in the field of detecting contaminants has led to smaller systems that provide faster and more effective ways for diagnosis purposes. In this study, a novel portable amperometric graphene oxide–protein biosensor platform is investigated. The main characteristic of this structure is the implementation of a microfluidic configuration. With albumin metalloprotein as the biorecognition element, graphene oxide was synthesized and characterized by transmission electron...
A novel model for predicting bioelectrochemical performance of microsized-MFCs by incorporating bacterial chemotaxis parameters and simulation of biofilm formation
, Article Bioelectrochemistry ; Volume 122 , 2018 , Pages 51-60 ; 15675394 (ISSN) ; Mardanpour, M. M ; Yaghmaei, S ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Bacterial transport parameters play a fundamental role in microbial population dynamics, biofilm formation and bacteria dispersion. In this study, the novel model was extended based on the capability of microsized microbial fuel cells (MFCs) as amperometric biosensors to predict the cells' chemotactic and bioelectrochemical properties. The model prediction results coincide with the experimental data of Shewanella oneidensis and chemotaxis mutant of P. aeruginosa bdlA and pilT strains, indicating the complementary role of numerical predictions for bioscreening applications of microsized MFCs. Considering the general mechanisms for electron transfer, substrate biodegradation, microbial growth...