Amperometric Glucose Biosensor Research Articles

Covalent Immobilization of Glucose Oxidase onto Electro-synthesized Nanocomposite with PEDOT Derivative for Amperometric Glucose Biosensing

Covalent Immobilization of Glucose Oxidase onto Electro-synthesized Nanocomposite with PEDOT Derivative for Amperometric Glucose Biosensing

Preparation of magnetic Fe3O4/PPy@ZIF-8 nanocomposite for glucose oxidase immobilization and used as glucose electrochemical biosensor

The MOFs (ZIF-8) coated Fe3O4/PPy magnetic nanocomposite (Fe3O4/PPy@ZIF-8) with large surface area and high conductivity was successfully prepared by polymerizing the pyrrole on Fe3O4 nanoparticle and self-assembling the ZIF-8 on the composite. Due to the outstanding specific area and pore volume of MOFs on the resulted nanocomposite, the glucose oxidase (GOx) could be effectively immobilized on the Fe3O4/PPy@ZIF-8 to fabricate a novel amperometric glucose biosensor. The as-prepared GOx/Fe3O4/PPy@ZIF-8/GCE biosensor exhibited extraordinary electro-detection performance for glucose with wide linear range from 1 μM to 2 mM and the limit of detection was 0.333 μM (S/N = 3). Furthermore, the prepared biosensor also showed good selectivity for glucose detection and satisfactory result in real samples detection.

Facile hydrothermal synthesis of mn doped ZnO nanopencils for development of amperometric glucose biosensors

Mn doped ZnO nanopencils were synthesized via low temperature hydrothermal process for fabrication of enzymatic electrochemical glucose biosensor. The KMnO4 was found to play a dual role in modifying morphology and inducing Mn doping. Interestingly, two different types of morphologies viz nanorods and nanopencils along with Mn doping in the later were obtained. Incorporation of Mn has shown a tremendous effect on the morphological variations, repression of defects and electrochemical charge transfer at electrode electrolyte interface. The possible reason behind obtained morphological changes has been proposed which in turn were responsible for the improvement in the different figure of merits of as fabricated enzymatic electrochemical biosensor. There has been a 17 fold enhancement in the sensitivity of the as fabricated glucose biosensor from ZnO nanorods to Mn doped ZnO nanopencils which can be attributed to morphological variation and Mn doping.

An Amperometric Glucose Biosensor Based on Poly (Pyrrole‐2‐Carboxylic Acid)/Glucose Oxidase Biocomposite

AbstractA newly developed amperometric glucose biosensor based on graphite rod (GR) working electrode modified with biocomposite consisting of poly (pyrrole‐2‐carboxylic acid) (PCPy) particles and enzyme glucose oxidase (GOx) was investigated. The PCPy particles were synthesized by chemical oxidative polymerization technique using H2O2 as initiator of polymerization reaction and modified covalently with the GOx (PCPy‐GOx) after activation of carboxyl groups located on the particles surface with a mixture of N‐(3‐dimethylaminopropyl)‐N′‐ethylcarbodiimide hydrochloride (EDC) and N‐hydroxysuccinimide (NHS). Then the PCPy‐GOx biocomposite was dispersed in a buffer solution containing a certain amount of bovine serum albumin (BSA). The resulting biocomposite suspension was adsorbed the on GR electrode surface with subsequent solvent airing and chemical cross‐linking of the proteins with glutaraldehyde vapour (GR/PCPy‐GOx). It was determined that the current response of the GR/PCPy‐GOx electrodes to glucose measured at +300 mV vs Cl reference electrode was influenced by the duration of the PCPy particles synthesis, pH of the GOx solution used for the PCPy particles modification and the amount of immobilized PCPy‐GOx biocomposite. An optimal pH of buffer solution for operation of the biosensor was found to be 8.0. Detection limit was determined as 0.039 mmol L−1 according signal to noise ratio (S/N: 3). The proposed glucose biosensor was tested in human serum samples.

Newly Designed Amperometric Biosensor for Hydrogen Peroxide and Glucose Based on Vanadium Sulfide Nanoparticles

In the present work, we describe a facile, green, and template-free solvothermal fabrication of vanadium sulfide (VS2) nanoparticles (NPs) and their application for the electrochemical detection of hydrogen peroxide (H2O2) and glucose. The morphology and composition of as-prepared samples were well-characterized by powder X-ray diffraction, energy-dispersive spectroscopy, transmission electron microscopy, scanning electron microscopy, UV–vis spectroscopy, and Brunauer–Emmett–Teller surface area measurement. Because of their interesting electrochemical responses toward H2O2, a novel nonenzymatic electrochemical sensor for H2O2 and glucose detection has been proposed based on a VS2 NP-modified glassy carbon electrode. The modified electrode showed an excellent electrochemical performance for the selective and sensitive nonenzymatic detection of H2O2 in a broad concentration range of 0.5 μM to 3.0 mM, with a wide linear range of 0.5 μM to 2.5 mM and a lower detection limit of 0.224 μM. The newly developed se...

3D nitrogen-doped graphite foam@Prussian blue: an electrochemical sensing platform for highly sensitive determination of H2O2 and glucose.

A platform is described for voltammetric sensing of hydrogen peroxide (H2O2). It is based on the use of nitrogen-doped graphite foam modified with Prussian Blue particles (PB/NGF). Graphite foam was synthesized by chemical vapor deposition, and doping with nitrogen was realized via dielectric barrier plasma discharge. PB particles were grown on the NGF through electrodeposition. SEM images of NGF verified the porous and interconnected structure of graphite foam, and XPS and Raman spectroscopy verified the successful doping with N. The performance of the PB/NGF electrode was characterized by CV and EIS which showed it to possess outstanding properties in terms of sensing H2O2. H2O2 was quantified in a range of 0.004 to 1.6mM with a detection limit of 2.4μM. The PB/NGF electrode also is shown to be a viable substrate for loading glucose oxidase (GOx). The GOx-functionalized electrode responds to glucose over the 0.2 to 20mM concentration range at a potential of -50mV (vs. Ag/AgCl), with a sensitivity of 27.48mA M-1cm-2 and a 0.1M detection limit (at an S/N ratio of 3). The glucose sensor is selective, stable, and reproducible. The biosensor was successfully applied to the determination of glucose in spiked human serum samples, and this confirmed it practicability. Graphical abstract Schematic of a self-supporting amperometric glucose biosensor based on glucose oxidase and Prussian blue modified 3D nitrogen doped graphite foam.

Using Response Surface Methodology for Amperometric Glucose Biosensor Construction

In this study, construction of amperometric glucose biosensor was carried out by immobilizing of
 glucose oxidase (GOD) on platinum electrode with 0.09 cm2 surface area which coated with
 polypyrrole (PPy) by cyclic voltammetry technique. Because measured current values in the
 presence of glucose would be affected from the electrode preparing and working conditions,
 experimental parameters should be optimized by response surface methodology (RSM). To this,
 State Ease Design Expert 8.0.7.1. (Serial Number:0021-6578) programe was used. PPy synthesis
 conditions of pyrrole (Py) monomer concentration and scan rate were optimized according to
 current response in presence of glucose. Optimal Py monomer concentration and scan rate for PPy
 synthesis were determined as 10 mM and 50 mV/s, respectively. Immobilization parameters such
 as concentrations of chitosan, GOD and glutaraldehyde (GAL) also were optimized by RSM as 1.0
 %, 4 mg/ml and 0.0625 %, respectively. The digital photos of electrodes at each stage were
 obtained. All electrodes well characterized in absence and in the presence of glucose by cyclic
 voltammetry and impedance techniques and it was observed that electrodes were sensitive to
 glucose molecule. Finally the effect of working pH and applied potential on the current response
 was investigated by RSM. The highest current response was obsreved when pH of glucose solution
 and applied potential were 6.0 and 0.8, respectively.

Development of an Amperometric Glucose Biosensor Based on the Immobilization of Glucose Oxidase on the Se-MCM-41 Mesoporous Composite.

A new bioenzymatic glucose biosensor for selective and sensitive detection of glucose was developed by the immobilization of glucose oxidase (GOD) onto selenium nanoparticle-mesoporous silica composite (MCM-41) matrix and then prepared as a carbon paste electrode (CPE). Cyclic voltammetry was employed to probe the catalytic behavior of the biosensor. A linear calibration plot is obtained over a wide concentration range of glucose from 1 × 10−5 to 2 × 10−3 M. Under optimal conditions, the biosensor exhibits high sensitivity (0.34 µA·mM−1), low detection limit (1 × 10−4 M), high affinity to glucose (Km = 0.02 mM), and also good reproducibility (R.S.D. 2.8%, n=10) and a stability of about ten days when stored dry at +4°C. Besides, the effects of pH value, scan rate, mediator effects on the glucose current, and electroactive interference of the biosensor were also discussed. As a result, the biosensor exhibited an excellent electrocatalytic response to glucose as well as unique stability and reproducibility.

An amperometric glucose biosensor based on PEDOT nanofibers.

Here we present a simple, low cost approach for the production of PEDOT nanofiber biosensors using simple techniques. Firstly, nanofibers of PEDOT were produced by the chemical vapor polymerization of EDOT on FeCl3 containing electrospun PAN nanofiber mats. The nanofibers were characterized by SEM, FTIR, CV and conductivity studies, which indicated the formation of homogeneous, porous, electroactive PEDOT nanofibers. The fabrication of biosensors was achieved through the loading of various amounts of GOx on the nanofibers. To uncover their capability, the biosensors were operated under both hydrogen peroxide production and oxygen consumption conditions. For each biosensor current response versus glucose concentration calibration curves were plotted. The sensitivity, linear range, LOD, Km and Imax values of the biosensors were determined and the stabilities of all the sensors were investigated. The biosensor operating at 0.6 V revealed a lower LOD with a wider linear range, higher stability, good sensitivity and selectivity. For example, the PEDOT-NFs/GOx-3 nanofiber biosensor showed good sensitivity (74.22 μA mM−1 cm−2) and LOD (2.9 μM) with a response time of 2–3 s without any interference effects. The PEDOT-NFs/GOx-2 biosensor operating at −0.6 V exhibited extreme sensitivity of 272.58 μA mM−1 cm−2. Our studies have shown that having good sensitivity, LOD and stability makes these interference-free, easy to construct sensors viable candidates for commercialization.

Carbon paste electrode based on functional GOx/silica-lignin system to prepare an amperometric glucose biosensor

In this paper, a novel procedure for receiving enzyme biosensor based on the cheap and functional silica/lignin (SiO2/Lig) hybrid material is presented. In this study, a functional biohybrid SiO2/Lig was selected to conduct the immobilization of glucose oxidase (GOx) by adsorption on its surface. The immobilized amount of GOx at SiO2/Lig was 25.28mgg−1, twice as much compared to its amount at non-functionalized SiO2. The system of GOx-SiO2/Lig was combined with single-walled carbon nanotubes/platinum nanoparticles support to prepare a I generation glucose biosensor. Moreover, the GOx-SiO2/Lig based carbon paste electrode with ferrocene redox mediator was evaluated as an active material in II generation glucose biosensor. The GOx-SiO2/Lig/CPE was subjected to an examination in glucose solution by electrochemical techniques such as cyclic voltammetry (CV) and chronoamperometry. The obtained results suggest that GOx-SiO2/Lig can be a material of choice for preparation of an efficient and low-cost biosensor working in various electrode configurations. The newly obtained glucose biosensor presents promising electrochemical parameters for glucose determination. The glucose-sensing sensitivity amounted 0.78μAmM−1. The biosensor showed a linear response range of 0.5–9mM with a detection limit (LOD) of 145μM.

Plasma-modified multiwalled carbon nanotubes with polyaniline for glucose biosensor applications

ABSTRACTMultiwalled carbon nanotube (MWCNT) was modified through plasma polymerization of aniline by applying different radio frequency (radio frequency (RF): 13.56 MHz) powers. The modified MWCNTs were investigated in terms of morphology, chemical structure, and thermal behaviors, indicating the formation of composites based on the surface modification of MWCNT with polyaniline (PANI). These composites were then used in amperometric glucose biosensor, which was constructed by immobilizing glucose oxidase on premodified Pt electrode with PANI/MWCNT composites. The biosensor based on the composite obtained under RF power of 60 W exhibited the high sensitivity of 54.91 µA mM−1 cm−2 to glucose.

Physical and Electrochemical Properties of Iron Oxide Nanoparticles-modified Electrode for Amperometric Glucose Detection

A high-sensitivity amperometric glucose biosensor was developed using iron oxide nanoparticles (IONPs), glucose oxidase (GOx) enzyme, and Nafion layer immobilized on screen-printed carbon electrode (SPCE) (Nafion/GOx/IONPs/SPCE). IONPs were synthesized through precipitation and functionalized with citric acid (CA) to provide a hydrophilic surface and functional groups for immobilization of the GOx enzyme. The transmission electron microscopy image showed that size of the obtained IONPs is ∼20nm. The X-ray diffraction pattern showed the presence of spinel cubic lattice of maghemite (γ-Fe2O3). Under the optimal condition, the amperometric responses of the resulting bioelectrode Nafion/GOx/CA-IONPs/SPCE presented high sensitivities of 175 and 5.31μAmM−1cm−2 for the detection of 0.02–0.25 and 0.25–8.00mM glucose, respectively. The biosensor exhibited low limit of detection of 7μM, good repeatability by maintaining 93% of the initial peak current after 10 cycles of cyclic voltammetry measurement, and sufficient reproducibility of 4.2% (number of sensors n=7). The fabricated amperometric biosensor features high sensitivity, disposability, low cost, and simple procedure for glucose detection.

Influence of aspect ratio and surface defect density on hydrothermally grown ZnO nanorods towards amperometric glucose biosensing applications

In this work, hydrothermally grown ZnO Nanorods Array (ZNA) has been synthesized over Platinum (Pt) coated glass substrate, for biosensing applications. In-situ addition of strong oxidizing agent viz KMnO4 during hydrothermal growth was found to have profound effect on the physical properties of ZNA. Glucose oxidase (GOx) was later immobilized over ZNA by means of physical adsorption process. Further influence of varying aspect ratio, enzyme loading and surface defects on amperometric glucose biosensor has been analyzed. Significant variation in biosensor performance was observed by varying the amount of KMnO4 addition during the growth. Moreover, investigations revealed that the suppression of surface defects and aspect ratio variation of the ZNA played key role towards the observed improvement in the biosensor performance, thereby significantly affecting the sensitivity and response time of the fabricated biosensor. Among different biosensors fabricated having varied aspect ratio and surface defect density of ZNA, the best electrode resulted into sensitivity and response time to be 18.7mAcm−2M−1 and <5s respectively. The observed results revealed that apart from high aspect ratio nanostructures and the extent of enzyme loading, surface defect density also hold a key towards ZnO nanostructures based bio-sensing applications.

Fast Fourier transformation electrochemical impedance spectroscopy for the investigation of inactivation of glucose biosensor based on graphite electrode modified by Prussian blue, polypyrrole and glucose oxidase

In this study we report the application of fast Fourier transformation electrochemical impedance spectroscopy (FFT-EIS) for the evaluation of bioselective layer of amperometric glucose biosensor created by the entrapment of the enzyme glucose oxidase (GOx) within composite polypyrrole (Ppy) and Prussian blue (PB) based layer. Additionally, chronoamperometry and atomic force microscopy (AFM) were applied for the characterization of graphite electrodes (GE) modified with bioselective layer of PB/Ppy/GOx. AFM investigations reveal that the variation of pyrrole concentration in the range of 10–30mM did not show significant differences in the surface roughness because calculated root mean square (RMS) was in the range of 15–19nm. In another set of experiments, which were based on FFT-EIS, only a small variation in charge transfer resistance was observed before and after application of GE/PB/Ppy/GOx electrodes for amperometric determination of glucose concentration. These findings preliminary suggest that those electrochemical properties of GE/PB/Ppy/GOx electrode, which could be detected by FFT-EIS method, do not vary significantly during the use of this electrode in the detection of glucose. However, the amperometric signals of the GE/PB/Ppy/GOx electrodes decrease during the measurements due to the mixed-type of GOx inhibition, as it was determined by the evaluation of cathodic currents vs glucose concentrations. These evaluations of amperometric response kinetics let us suggest that the decrease of biosensor signal is based on mixed-type (uncompetitive and non-competitive) inhibition of GOx.

Development of Frequency Based Taste Receptors Using Bioinspired Glucose Nanobiosensor

A method to fabricate a bioinspired nanobiosensor using electronic-based artificial taste receptors for glucose diagnosis is presented. Fabricated bioinspired glucose nanobiosensor designated based on an artificial taste bud including an amperometric glucose biosensor and taste bud-inspired circuits. In fact, the design of the taste bud-inspired circuits was inspired by the signal-processing mechanism of taste nerves which involves two layers. The first, known as a type II cell, detects the glucose by glucose oxidase and transduces the current signal obtained for the pulse pattern is conducted to the second layer, called type III cell, to induce synchronisation of the neural spiking activity. The oscillation results of fabricated bioinspired glucose nanobiosensor confirmed an increase in the frequency of the output pulse as a function of the glucose concentration. At high glucose concentrations, the bioinspired glucose nanobiosensor showed a pulse train of alternating short and long interpulse intervals. A computational analysis performed to validate the hypothesis, which was successfully reproduced the alternating behaviour of bioinspired glucose our nanobiosensor by increasing the output frequency and alternation of pulse intervals according to the reduction in the resistivity of the biosensor.

Reagent-less amperometric glucose biosensor based on a graphite rod electrode layer-by-layer modified with 1,10-phenanthroline-5,6-dione and glucose oxidase

A reagent-less amperometric glucose biosensor operating in not-stirred sample solution was developed. A working electrode of the designed biosensor was based on a graphite rod (GR) electrode, which was modified with 1,10-phenanthroline-5,6-dione (PD) and glucose oxidase (GOx). The PD and the GOx were layer-by-layer adsorbed on the GR electrode surface with subsequent drying followed by chemical cross-linking of the adsorbed GOx with glutaraldehyde (GA). Optimal preparation conditions of the working electrode (GR/PD/GOx) were achieved with 12.6μg and 0.24mg loading amount of PD and GOx, respectively and 25min lasting cross-linking of the GOx with GA. A current response to glucose of the GR/PD/GOx electrode was measured at +200mV potential vs Ag/AgCl reference electrode. Maximum current response was registered when the pH of the buffer solution was 6.0. The registered current response to glucose was linear in the concentration range of 0.1–76mmolL–1 (R2=0.9985) and a detection limit was 0.025mmolL–1. The GR/PD/GOx electrode demonstrated good reproducibility and repeatability with the relative standard deviation of 6.2% and 1.8% (at 4.0mmolL–1 of glucose), respectively, high anti-interference ability to uric and ascorbic acids. It was highly selective to glucose and demonstrated good accuracy in the analysis of human serum samples.

Amperometric glucose biosensor based on immobilization of glucose oxidase on a magnetic glassy carbon electrode modified with a novel magnetic nanocomposite

We present a method to produce a magnetic glassy carbon electrode (MGCE) modified with multilayer nanocomposite (Ag@MWCNT-IL-Fe3O4) as an immobilization support to promote electron transfer reactions of glucose oxidase (GOx). The nanocomposite verified by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and a vibrating sample magnetometer (VSM). The direct electron transfer (DET) between GOx and Ag@MWCNT-IL-Fe3O4 nanocomposite was investigated using cyclic voltammetry which showed a pair of well-defined redox peaks corresponding to redox active center of GOx. Utilization of constructed electrode for detection of glucose was studied in N2 and air saturated solutions (pH 7.0). The GOx/Ag@MWCNT-IL-Fe3O4/MGCE showed excellent stability, a detection limit of 2.12μM, a linear range between 6μM and 2mM, and a dynamic range up to 2.7mM at the air saturated solutions. Also, in N2 saturated solutions (pH 7.0), determination of glucose was carried out by amperometry, and the proposed biosensor showed good reproducibility and stability with a detection limit of 3.8μM and a linear range between 10μM and 1mM. Such analytical performances confirm that the fabricated biosensor used in this work has potential to be applied for development of redox enzyme based biosensors.

Amperometric Glucose Biosensor Based on Electrochemically Deposited Gold Nanoparticles Covered by Polypyrrole

AbstractGraphite rod (GR) modified with electrochemicaly deposited gold nanoparticles (AuNPs) and adsorbed glucose oxidase (GOx) was used in amperometric glucose biosensor design. Enzymatic formation of polypyrrole (Ppy) on the surface of GOx/AuNPs/GR electrode was applied in order to improve analytical characteristics and stability of developed biosensor. The linear glucose detection range for Ppy/GOx/AuNPs/GR electrode was dependent on the duration of Ppy‐layer formation and the linear interval was extended up to 19.9 mmol L−1 after 21 h lasting synthesis of Ppy. The sensitivity of the developed biosensor was determined as 21.7 μA mM−1 cm−2, the limit of detection – 0.20 mmol L−1. Ppy/GOx/AuNPs/GR electrodes demonstrated advanced good stability (the t1/2 was 9.8 days), quick detection of glucose (within 5 s) in the wide linear interval. Additionally, formed Ppy layer decreased the influence of electroactive species on the analytical signal. Developed biosensor is suitable for the determination of glucose in human serum samples.

Amperometric detection of glucose in fruit juices with polypyrrole-based biosensor with an integrated permselective layer for exclusion of interferences.

A novel polypyrrole (PPy)-based bilayer amperometric glucose biosensor integrated with a permselective layer has been developed for detection of glucose in the presence of interferences. It comprises of a PPy-GOx film grown, in the absence of electrolyte, as an inner layer, and a permselective PPy-Cl film as an outer layer. The PPy-GOx/PPy-Cl bilayer biosensor was effective in rejecting 98% of ascorbic acid and 100% of glycine, glutamic acid and uric acid. With an outer layer thickness of 6.6nm, the bilayer biosensor gave nearly identical glucose response to that of a single layer PPy-GOx biosensor. The biosensor also exhibited good reproducibility (1.9% rsd, n=10), high stability (more than 2months), wide linear range (0.5-24mM), low Km (8.4mM), high Imax (77.2μAcm-2), low detection limit (26.9μM) and good sensitivity (3.5μAcm-2mM-1). The bilayer biosensor was successfully employed for glucose determination in various fruit juices.

Amperometric Glucose Biosensor Based on AuPd Modified Reduced Graphene Oxide/Polyimide Film with Glucose Oxidase

AuPd bimetallic composite has been prepared on reduced graphene oxide/polyimide (PI/RGO) film by electrodeposition. The AuPd fabricated on PI/RGO film exhibits good conductivity and excellent catalytic properties. AuPd/PI/RGO electrode shows high activity toward hydrogen peroxide (H2O2) for coupling effect between AuPd and PI/RGO film. Based on high electrochemical activity toward H2O2, an amperometric glucose biosensor has been also described, which was achieved by the immobilization of glucose oxidase (GOx) onto the AuPd/PI/RGO electrode. The proposed biosensor displayed good amperometric response characteristics toward glucose, such as a fast response within 3 s and a wide linear range from 0.024 mM to 4.6 mM. In addition, the biosensor was utilized for the detection of glucose in human blood serum that displayed satisfactory results. The present finding might open up a new avenue in the development of high performance bimetallic materials on appropriate supporting materials for electrochemical sensing.