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Glucose biosensor based on platinum nanoparticles supported sulfonated-carbon nanotubes modified glassy carbon electrode
H.J. Wang, C.M. Zhou, F. Peng, H. Yu
International Journal of Electrochemical Science , 2007,
Abstract: Highly dispersed Pt nanoparticles supported on sulfonated multiwalled carbon nanotubes (Pt/sulfonated-MWCNTs) were used to modify glassy carbon (GC) electrode and then glucose oxidase was immobilized on the Pt/sulfonated-MWCNTs/GC electrode to construct a GOD/Pt/sulfonated-MWCNTs/GC glucose biosensor. The electrochemical and detection performance were evaluated by cyclic voltammogram and chronoamperometry. The optimum detection conditions were determined and the stability was studied. The results show that the GOD/Pt/sulfonated-MWCNTs/GC glucose biosensor has much higher detection sensitivity of 0.56 μA/mM and much larger linear range up to 6.4 mM at rather lower working potential of 0.5 V. It can keep more than 85% of its initial activity after continuously using one hour. The results show that the resultant GOD/Pt/sulfonated-MWCNTs/GC glucose biosensor has high electrocatalytic activity and excellent detecting performance for glucose.
Glucose Biosensor Based on a Glassy Carbon Electrode Modified with Polythionine and Multiwalled Carbon Nanotubes  [PDF]
Wenwei Tang, Lei Li, Lujun Wu, Jiemin Gong, Xinping Zeng
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0095030
Abstract: A novel glucose biosensor was fabricated. The first layer of the biosensor was polythionine, which was formed by the electrochemical polymerisation of the thionine monomer on a glassy carbon electrode. The remaining layers were coated with chitosan-MWCNTs, GOx, and the chitosan-PTFE film in sequence. The MWCNTs embedded in FAD were like “conductive wires” connecting FAD with electrode, reduced the distance between them and were propitious to fast direct electron transfer. Combining with good electrical conductivity of PTH and MWCNTs, the current response was enlarged. The sensor was a parallel multi-component reaction system (PMRS) and excellent electrocatalytic performance for glucose could be obtained without a mediator. The glucose sensor had a working voltage of ?0.42 V, an optimum working temperature of 25°C, an optimum working pH of 7.0, and the best percentage of polytetrafluoroethylene emulsion (PTFE) in the outer composite film was 2%. Under the optimised conditions, the biosensor displayed a high sensitivity of 2.80 μA mM?1 cm?2 and a low detection limit of 5 μM (S/N = 3), with a response time of less than 15 s and a linear range of 0.04 mM to 2.5 mM. Furthermore, the fabricated biosensor had a good selectivity, reproducibility, and long-term stability, indicating that the novel CTS+PTFE/GOx/MWCNTs/PTH composite is a promising material for immobilization of biomolecules and fabrication of third generation biosensors.
Electrochemical Glucose Sensors—Developments Using Electrostatic Assembly and Carbon Nanotubes for Biosensor Construction  [PDF]
Alice Harper,Mark R. Anderson
Sensors , 2010, DOI: 10.3390/s100908248
Abstract: In 1962, Clark and Lyons proposed incorporating the enzyme glucose oxidase in the construction of an electrochemical sensor for glucose in blood plasma. In their application, Clark and Lyons describe an electrode in which a membrane permeable to glucose traps a small volume of solution containing the enzyme adjacent to a pH electrode, and the presence of glucose is detected by the change in the electrode potential that occurs when glucose reacts with the enzyme in this volume of solution. Although described nearly 50 years ago, this seminal development provides the general structure for constructing electrochemical glucose sensors that is still used today. Despite the maturity of the field, new developments that explore solutions to the fundamental limitations of electrochemical glucose sensors continue to emerge. Here we discuss two developments of the last 15 years; confining the enzyme and a redox mediator to a very thin molecular films at electrode surfaces by electrostatic assembly, and the use of electrodes modified by carbon nanotubes (CNTs) to leverage the electrocatalytic effect of the CNTs to reduce the oxidation overpotential of the electrode reaction or for the direct electron transport to the enzyme.
Simple Method for Preparing Glucose Biosensor Based on Glucose Oxidase in Nanocomposite Material of Single-Wall Carbon Nanotubes/Ionic Liquid  [PDF]
Weina Wang, Guang Yin, Xiuju Ma, Jun Wan
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2012, DOI: 10.4236/jasmi.2012.22011
Abstract: Based on electric conductivity and wide potential window of ionic liquid (IL) and electric property of single-wall car- bon nanotubes (SWCNTs), composite material of IL-SWCNTs was prepared, glucose sensor was built with this mate-rial for immobilizing glucose oxidase (GOx). It showed good response, sensitivity and stability for long time for glu-cose detection. Linear range for the detection of glucose was from 0.5 × 10–6 M to 12 × 10–6 M while detection limit was 6.26 × 10–8 M (S/N = 3).
Carbon nanotube composites for glucose biosensor incorporated with reverse iontophoresis function for noninvasive glucose monitoring  [cached]
Tai-Ping Sun,Hsiu-Li Shieh,Congo Tak-Shing Ching,et al
International Journal of Nanomedicine , 2010,
Abstract: Tai-Ping Sun1,2,5, Hsiu-Li Shieh2, Congo Tak-Shing Ching1,2,5, Yan-Dong Yao3, Su-Hua Huang4, Chia-Ming Liu1, Wei-Hao Liu1, Chung-Yuan Chen21Graduate Institute of Biomedicine and Biomedical Technology, 2Department of Electrical Engineering, National Chi Nan University, Nantou, Taiwan, ROC; 3Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong; 4Department of Biotechnology, Asia University, Taichung, Taiwan, ROC; 5These authors contributed equally to this workAbstract: This study aims to develop an amperometric glucose biosensor, based on carbon nanotubes material for reverse iontophoresis, fabricated by immobilizing a mixture of glucose oxidase (GOD) and multiwalled carbon nanotubes (MWCNT) epoxy-composite, on a planar screen-printed carbon electrode. MWCNT was employed to ensure proper incorporation into the epoxy mixture and faster electron transfer between the GOD and the transducer. Results showed this biosensor possesses a low detection potential (+500 mV), good sensitivity (4 μA/mM) and an excellent linear response range (r2 = 0.999; 0–4 mM) of glucose detection at +500 mV (versus Ag/AgCl). The response time of the biosensor was about 25 s. In addition, the biosensor could be used in conjunction with reverse iontophoresis technique. In an actual evaluation model, an excellent linear relationship (r2 = 0.986) was found between the glucose concentration of the actual model and the biosensor’s current response. Thus, a glucose biosensor based on carbon nanotube composites and incorporated with reverse iontophoresis function was developed.Keywords: amperometric, carbon nanotubes, glucose monitoring, biosensors, reverse iontophoresis
Carbon nanotube composites for glucose biosensor incorporated with reverse iontophoresis function for noninvasive glucose monitoring
Tai-Ping Sun, Hsiu-Li Shieh, Congo Tak-Shing Ching, et al
International Journal of Nanomedicine , 2010, DOI: http://dx.doi.org/10.2147/IJN.S10247
Abstract: rbon nanotube composites for glucose biosensor incorporated with reverse iontophoresis function for noninvasive glucose monitoring Original Research (5344) Total Article Views Authors: Tai-Ping Sun, Hsiu-Li Shieh, Congo Tak-Shing Ching, et al Published Date May 2010 Volume 2010:5 Pages 343 - 349 DOI: http://dx.doi.org/10.2147/IJN.S10247 Tai-Ping Sun1,2,5, Hsiu-Li Shieh2, Congo Tak-Shing Ching1,2,5, Yan-Dong Yao3, Su-Hua Huang4, Chia-Ming Liu1, Wei-Hao Liu1, Chung-Yuan Chen2 1Graduate Institute of Biomedicine and Biomedical Technology, 2Department of Electrical Engineering, National Chi Nan University, Nantou, Taiwan, ROC; 3Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong; 4Department of Biotechnology, Asia University, Taichung, Taiwan, ROC; 5These authors contributed equally to this work Abstract: This study aims to develop an amperometric glucose biosensor, based on carbon nanotubes material for reverse iontophoresis, fabricated by immobilizing a mixture of glucose oxidase (GOD) and multiwalled carbon nanotubes (MWCNT) epoxy-composite, on a planar screen-printed carbon electrode. MWCNT was employed to ensure proper incorporation into the epoxy mixture and faster electron transfer between the GOD and the transducer. Results showed this biosensor possesses a low detection potential (+500 mV), good sensitivity (4 μA/mM) and an excellent linear response range (r2 = 0.999; 0–4 mM) of glucose detection at +500 mV (versus Ag/AgCl). The response time of the biosensor was about 25 s. In addition, the biosensor could be used in conjunction with reverse iontophoresis technique. In an actual evaluation model, an excellent linear relationship (r2 = 0.986) was found between the glucose concentration of the actual model and the biosensor’s current response. Thus, a glucose biosensor based on carbon nanotube composites and incorporated with reverse iontophoresis function was developed.
Modelling Carbon Nanotubes-Based Mediatorless Biosensor  [PDF]
Romas Baronas,Juozas Kulys,Karolis Petrauskas,Julija Razumiene
Sensors , 2012, DOI: 10.3390/s120709146
Abstract: This paper presents a mathematical model of carbon nanotubes-based mediatorless biosensor. The developed model is based on nonlinear non-stationary reaction-diffusion equations. The model involves four layers (compartments): a layer of enzyme solution entrapped on a terylene membrane, a layer of the single walled carbon nanotubes deposited on a perforated membrane, and an outer diffusion layer. The biosensor response and sensitivity are investigated by changing the model parameters with a special emphasis on the mediatorless transfer of the electrons in the layer of the enzyme-loaded carbon nanotubes. The numerical simulation at transient and steady state conditions was carried out using the finite difference technique. The mathematical model and the numerical solution were validated by experimental data. The obtained agreement between the simulation results and the experimental data was admissible at different concentrations of the substrate.
Graphene versus Multi-Walled Carbon Nanotubes for Electrochemical Glucose Biosensing  [PDF]
Dan Zheng,Sandeep Kumar Vashist,Michal Marcin Dykas,Surajit Saha,Khalid Al-Rubeaan,Edmond Lam,John H.T. Luong,Fwu-Shan Sheu
Materials , 2013, DOI: 10.3390/ma6031011
Abstract: : A simple procedure was developed for the fabrication of electrochemical glucose biosensors using glucose oxidase (GOx), with graphene or multi-walled carbon nanotubes (MWCNTs). Graphene and MWCNTs were dispersed in 0.25% 3-aminopropyltriethoxysilane (APTES) and drop cast on 1% KOH-pre-treated glassy carbon electrodes (GCEs). The EDC (1-ethyl-(3-dimethylaminopropyl) carbodiimide)-activated GOx was then bound covalently on the graphene- or MWCNT-modified GCE. Both the graphene- and MWCNT-based biosensors detected the entire pathophysiological range of blood glucose in humans, 1.4–27.9 mM. However, the direct electron transfer (DET) between GOx and the modified GCE’s surface was only observed for the MWCNT-based biosensor. The MWCNT-based glucose biosensor also provided over a four-fold higher current signal than its graphene counterpart. Several interfering substances, including drug metabolites, provoked negligible interference at pathological levels for both the MWCNT- and graphene-based biosensors. However, the former was more prone to interfering substances and drug metabolites at extremely pathological concentrations than its graphene counterpart.
A Glucose-Responsive Enzymatic Electrode on Carbon Nanodots for Glucose Biosensor and Glucose/Air Biofuel Cell  [PDF]
Yue Gao, Guozhi Wu, Feng Gao
American Journal of Analytical Chemistry (AJAC) , 2019, DOI: 10.4236/ajac.2019.109027
Abstract: In this study, an enzymatic electrode for glucose biosensing and bioanode of glucose/air biofuel cell has been fabricated by immobilizing poly (methylene green) (polyMG) for electrocatalytic NADH oxidation and NAD+-dependent glucose dehydrogenase (GDH) for oxidizing glucose on carbon nanodots (CNDs). The polyMG-CNDscomposites obtained by electro-polymerization of dye MG molecules adsorbed on CNDs display excellent electrocatalytic activity toward NADH electro-oxidation at a low overpotential of ca. -0.10 V (vs. Ag/AgCl) and the integrated enzymatic electrode shows fast response to glucose electrooxidation. Using the fabricated GDH-based enzymatic electrode, a glucose biosensor was constructed and exhibits a wide linear dynamic range from 0 to 8 mM, a low detection limit of 0.02 μM (S/N = 3), and fast response time (ca. 4 s) under the optimized conditions. The developed glucose biosensor was used to detect glucose content in human blood with satisfactory results. The fabricated GDH-based enzymatic electrode was also employed as bioanode to assembly a glucose/air biofuel cell with the laccase-CNDs/GC as the biocathode. The maximum power density delivered by the assembled glucose/air biofuel cell reaches 3.1 μW·cm-2 at a cell voltage of 0.22 V in real sample fruit juice. The present study demonstrates that potential applications of GDH-based CNDs electrode in analytical and biomedical measurements.
Electrochemical Characterization of Streptavidin-HRP Immobilized on Multiwall Carbon Nanotubes for Biosensor Applications  [PDF]
Imene Hafaiedh, Hamdi Baccar, Taha Ktari, Adnane Abdelghani
Journal of Biomaterials and Nanobiotechnology (JBNB) , 2012, DOI: 10.4236/jbnb.2012.31005
Abstract: In this work, we used gold labeled multiwall carbons nanotubes for peroxidase biosensor. The gold labeling on multiwall carbon nanotubes can be achieved with Pressure vapor Deposition (PVD) technique. The obtained carbon nanotubes can be immobilized on gold electrode with the airbrushing technique. The stability and the molecular structure of the labeled multiwall carbon nanotubes were characterized with cyclic voltammetry, impedance spectroscopy and Fourrier Transform Infra-Red spectroscopy (FTIR). It shows a higher conductivity and a good stability in water interface. For streptavidin-HRP immobilization, the labeled gold nanotubes were activated over night with thiol-acid (16 carbons). An activation procedure was achieved with EDC/NHS for HRP-streptavidin immobilization. The development of biosensor for H2O2 detection was observed with the impedance spectroscopy and cyclic voltammetry techniques. This method could be used to determine total H2O2 concentration in the range 4 μM - 160 μM. The results show that the biosensor response depends on the conductivity and the large surface-to-volume ratio attained with multiwall carbon nanotubes. The response of the developed biosensors was reproducible with higher stability.
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