Amperometric glucose biosensor with high sensitivity based on self-assembled Prussian Blue modified electrode

A glucose biosensor, which was based on self-assembled Prussian Blue (PB) modified electrode with glucose oxidase (GOD) immobilized in cross-linked glutaraldehyde matrix, was developed. Fourier-transform infrared spectroscopy shows that the immobilized GOD retains its native conformation. Cyclic voltammetry was used to examine the electrocatalytic property of the enzyme electrode. The prepared glucose biosensor exhibits fast response (<4 s) and low detection limit of 5 × 10⁻⁶ M. The calculated apparent Michaelis constant K_M was 6.3 ± 1.2 mM, indicating a high affinity between the GOD and glucose. The effects of glutaraldehyde concentration and GOD loading on the sensitivity of the glucose biosensor have also been investigated. Under the optimal conditions, the biosensor shows a high sensitivity of about 80 mA M⁻¹ cm⁻² in a concentration range up to 1 × 10⁻³ M. The relative standard deviation (RSD) for intra-electrode and inter-electrode were 4% and 5%, respectively. In addition, the anti-interferent ability and stability of the biosensor were also discussed.     

Photoinducedly electrochemical preparation of Prussian blue film and electrochemical modification of the film with cetyltrimethylammonium cation

This work presents a photoinducedly electrochemical preparation of Prussian blue from a single sodium nitroprusside and insertion of cetyltrimethylammonium cations into Prussian blue as counter ions. The product of photoinducedly electrochemical reactions has a couple of voltammetric peaks at E° = 0.266 V in 0.2 mol l⁻¹ KCl solution, the measurements of X-ray powder diffraction and FT-IR spectroscopy show that it is Prussian blue (PB). The formation mechanism of a pre-photochemical reaction and subsequent electrochemical reaction is suggested. The cyclic voltammetric treatment of the freshly as-prepared PB film in 1.0 mmol l⁻¹ cetyltrimethylammonium (CTA) bromide solution leads to the insertion of cetyltrimethylammonium cations into the channels of Prussian blue, which substitutes for potassium ions as counter ions in Prussian blue. The Prussian blue containing CTA counter ions shows two couples of voltammetric peaks at E° = −0.106 V and E° = 0.249 V in 0.2 mol l⁻¹ KCl solution containing 1.0 mmol l⁻¹ cetyltrimethylammonium bromide. Compared with the electrochemical behaviors of KFeFe(CN)₆ in 0.1 mol l⁻¹ KOH alkali solution, CTAFeFe(CN)₆ shows relatively durable voltammetric currents due to the hydrophobic effects of cetyltrimethylammonium. The diffusion coefficients for CTA and potassium cations were estimated to be D_CTA 1.25 × 10⁻¹² cm² s⁻¹, D_K 2.59 × 10⁻¹² cm² s⁻¹, respectively. The peak current of electro-catalytic oxidization on hydrogen peroxide showed a linear dependence from 6.59 × 10⁻⁶ to 2.20 × 10⁻⁴ mol l⁻¹ with R = 0.99947 (n = 8). The linear regression equation was I_p (mA) = 0.82949 + 0.00594C (μmol l⁻¹) with errors of ±7.92833 × 10⁻⁵ for the slope and ±0.01085 for the intercept with the detection limit of 1.46 × 10⁻⁶ mol l⁻¹. Thus, it is expected to find its application in neutral or weak alkali medium for biosensors.     

Mechanism investigation of Prussian blue electrochemically deposited from a solution containing single component of ferricyanide

Prussian white (a reduced state of Prussian blue) was electrochemically deposited on a polycrystalline Pt electrode from an acidic solution of ferricyanide. Electrochemical measurements showed that the formation of Prussian white on platinum electrode was a self-terminated process. A compacted PB film can be formed by using both potential scanning and potentiostatic methods as confirmed by AFM measurement. In situ FTIR measurements were carried out to explore the formation mechanism. The new band arising at 2075 cm⁻¹ is assigned to the characteristic absorbance of CN of Prussian white, while the band at 2104 cm⁻¹ is due to the absorbance of CN of Prussian blue. A possible mechanism of electrodeposition of Prussian white was discussed.     

Study of the biosensor based on platinum nanoparticles supported on carbon nanotubes and sugar–lectin biospecific interactions for the determination of glucose

Highly sensitive electrochemical platform based on Pt nanoparticles supported on carbon nanotubes (Pt_nano-CNTs) and sugar–lectin biospecific interactions is developed for the direct electrochemistry of glucose oxidase (GOD). Firstly, Pt_nano-CNTs nanocomposites were prepared in the presence of carbon nanotubes (CNTs), and then the mixture was cast on a glassy carbon electrode (GCE) using chitosan as a binder. Thereafter, concanavalin A (Con A) was adsorbed onto the precursor film by the electrostatic force between positively charged chitosan and the negatively charged Con A. Finally, the multilayers of Con A/GOD films were prepared based on biospecific affinity of Con A and GOD via layer-by-layer (LBL) self-assembly technique. The electrochemical behavior of the sensor was studied using cyclic voltammetry and chronoamperometry. The electrochemical parameters of GOD in the film were calculated with the results of the electron transfer coefficient (α) and the apparent heterogeneous electron transfer rate constant (k_s) as 0.5 and 5.093 s⁻¹, respectively. Experimental results show that the biosensor responded linearly to glucose in the range from 1.2 × 10⁻⁶ to 2.0 × 10⁻³ M, with a detection limit of 4.0 × 10⁻⁷ M under optimized conditions.     

An ultrasensitive electrochemical biosensor for glucose using CdTe-CdS core–shell quantum dot as ultrafast electron transfer relay between graphene-gold nanocomposite and gold nanoparticle

The paper reported an ultrasensitive electrochemical biosensor for glucose which was based on CdTe-CdS core–shell quantum dot as ultrafast electron transfer relay between graphene-gold nanocomposite and gold nanoparticle. Since efficient electron transfer between glucose oxidase and the electrode was achieved, the biosensor showed high sensitivity (5762.8 nA nM⁻¹ cm⁻²), low detection limit (S/N = 3) (3 × 10⁻¹² M), fast response time (0.045 s), wide calibration range (from 1 × 10⁻¹¹ M to 1 × 10⁻⁸ M) and good long-term stability (26 weeks). The apparent Michaelis–Menten constant of the glucose oxidase on the medium, 5.24 × 10⁻⁶ mM, indicates excellent bioelectrocatalytic activity of the immobilized enzyme towards glucose oxidation. Moreover, the effects of omitting graphene-gold nanocomposite, CdTe-CdS core–shell quantum dot and gold nanoparticle were also investigated. The result showed sensitivity of the biosensor is 7.67-fold better if graphene-gold nanocomposite, CdTe-CdS core–shell quantum dot and gold nanoparticle are used. This could be ascribed to improvement of the conductivity between graphene nanosheets due to introduction of gold nanoparticles, ultrafast charge transfer from CdTe-CdS core–shell quantum dot to graphene nanosheets and gold nanoparticle due to unique electrochemical properties of the CdTe-CdS core–shell quantum dot and good biocompatibility of gold nanoparticle for glucose oxidase. The biosensor is of best sensitivity in all glucose biosensors based on graphene nanomaterials up to now and has been satisfactorily applied to determination of the glucose in human saliva samples.     

New effective process to fabricate fast switching and high contrast electrochromic device based on viologen and Prussian blue/antimony tin oxide nano-composites with dark colored state

We developed a new electrochromic device by using compact Prussian blue (PB)/antimony tin oxide (ATO) nano-composites as anodic electrode and viologen anchoring on titanium dioxide (TiO₂) nano-particles as cathodic electrode. The anodic electrode was based on a transparent nanostructured ATO nano-particle film and was electro-deposited by Prussian blue to form compact Prussian blue/ATO nano-composites by means of galvanostatic electrodeposition process. Nanocrystalline TiO₂ thin films on conducting glass were modified with a mono-layer of viologen with two anchoring groups, which were much strongly adsorbed onto the surface of TiO₂ nano-particles. A polymer gel electrolyte sandwiched between the anodic and cathodic layers is used as the ionic transport layer. The 2.5 cm × 2.5 cm electrochromic device shows high contrast (64.8%, at 600 nm) very low transmittance at colored stage (0.1%, at 600 nm), fast switching time (600 and 720 ms for coloration and bleaching, respectively), high coloration efficiency of 912 cm² C⁻¹ at 600 nm and good stability. The enhanced performance of the electrochromic device can be attributed to the ATO nano-particles as inter-conductive materials.     

Electrochemical detection of hydroquinone by graphene and Pt-graphene hybrid material synthesized through a microwave-assisted chemical reduction process

We have synthesized graphene and Pt-graphene hybrid material by a microwave-assisted chemical reduction process and evaluated their application as electrode materials towards the electrochemical detection of hydroquinone. Graphene modified glass carbon electrode (GCE) showed a good performance for detecting hydroquinone due to the unique properties of graphene which increased the active surface area of the electrode and accelerated the electron transfer. The linear detection range of hydroquinone concentration was 20–115 μM with a sensitivity of 1.38 μA μM⁻¹ cm⁻²; the detection limit was estimated to be 12 μM (S/N = 3). The electrocatalytic activity of the Pt-graphene modified GCE was further improved due to the enhanced electron transfer and the linear detection range was 20–145 μM with the sensitivity of 3.56 μA μM⁻¹ cm⁻², detection limit 6 μM (S/N = 3).     

Fabrication of graphene/prussian blue composite nanosheets and their electrocatalytic reduction of H2O2

In this work, graphene/prussian blue (PB) composite nanosheets with good dispersibility in aqueous solutions have been synthesized by mixing ferric-(III) chloride and potassium ferricyanide in the presence of graphene under ambient conditions. Transmission electron microscopy (TEM) shows that the average size of the as-synthesized PB nanoparticles on the surface of graphene nanosheets is about 20 nm. Fourier-transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) patterns have been used to characterize the chemical composition of the obtained graphene/PB composite nanosheets. The graphene/PB composite nanosheets exhibit good electrocatalytic behavior to detection of H₂O₂ at an applied potential of −0.05 V. The sensor shows a good linear dependence on H₂O₂ concentration in the range of 0.02-0.2 mM with a sensitivity of 196.6 μA mM⁻¹ cm⁻². The detection limit is 1.9 μM at the signal-to-noise ratio of 3. Furthermore, the graphene/PB modified electrode exhibits freedom of interference from other co-existing electroactive species. This work provides a new kind of composite modified electrode for amperometric biosensors.     

A new amperometric glucose biosensor based on platinum nanoparticles/polymerized ionic liquid-carbon nanotubes nanocomposites

A new amperometric glucose biosensor has been developed based on platinum (Pt) nanoparticles/polymerized ionic liquid-carbon nanotubes (CNTs) nanocomposites (PtNPs/PIL-CNTs). The CNTs was functionalized with polymerized ionic liquid (PIL) through directly polymerization of the ionic liquid, 1-vinyl-3-ethylimidazolium tetrafluoroborate ([VEIM]BF₄), on carbon nanotubes and then used as the support for the highly dispersed Pt nanoparticles. The electrochemical performance of the PtNPs/PIL-CNTs modified glassy carbon (PtNPs/PIL-CNTs/GC) electrode has been investigated by typical electrochemical methods. The PtNPs/PIL-CNTs/GC electrode shows high electrocatalytic activity towards the oxidation of hydrogen peroxide. Taking glucose oxidase (GOD) as the model, the resulting amperometric glucose biosensor shows good analytical characteristics, such as a high sensitivity (28.28 μA mM⁻¹ cm⁻²), wide linear range (up to 12 mM) and low detection limit (10 μM).     

Electrochemical detection of avian influenza virus H5N1 gene sequence using a DNA aptamer immobilized onto a hybrid nanomaterial-modified electrode

A sensitive electrochemical method for the detection of avian influenza virus (AIV) H5N1 gene sequence using a DNA aptamer immobilized onto a hybrid nanomaterial-modified electrode was developed. To enhance the selectivity and sensitivity, the modified electrode was assembled with multi-wall carbon nanotubes (MWNT), polypyrrole nanowires (PPNWs) and gold nanoparticles (GNPs). This electrode offered a porous structure with a large effective surface area, highly electrocatalytic activities and electronic conductivity. Therefore, the amount of DNA aptamer immobilized onto the electrode was increased while the accessibility of the detection target was maintained. The biosensor is based on the hybridization and preferred orientation of a DNA aptamer immobilized onto a modified electrode surface with its target (H5N1 specific sequence) present in solution. It is selective for the H5N1 specific sequence, and the signal of the indicator was approximately linear to log(concentration) of the H5N1 specific sequence from 5.0 × 10⁻¹² to 1.0 × 10⁻⁹ M (R = 0.9863) with a detection limit of 4.3 × 10⁻¹³ M. These studies showed that the new hybrid nanomaterial (MWNT/PPNWs/GNPs) and the DNA aptamer could be used to fabricate an electrochemical biosensor for gene sequence detection. Furthermore, this design strategy is expected to have extensive applications in other biosensors.     

A novel electrochemical DNA biosensor based on graphene and polyaniline nanowires

A novel DNA biosensor based on oxidized graphene and polyaniline nanowires (PANIws) modified glassy carbon electrode was developed. The resulting graphene/PANIw layers exhibited good DPV current response for the complementary DNA sequences. The good electron transfer activity might be attributed to the effect of graphene and PANIw. Graphene and PANIw nanolayers film with highly conductive and biocompatible nanostructure were characterized by scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The immobilization of the probe DNA on the surface of electrode was largely improved due to the unique synergetic effect of graphene and PANIw. Under optimum conditions, the biosensor exhibited a fast amperometric response, high sensitivity and good storage stability for monitoring DNA. The current response of the sensor increases linearly with the concentration of target from 2.12 × 10⁻⁶ to 2.12 × 10⁻¹² mol l⁻¹ with a relative coefficient of 0.9938. The detection limit (3σ) is 3.25 × 10⁻¹³ mol l⁻¹. The results indicate that this modified electrode has potential application in sensitive and selective DNA detection.     

Amperometric glucose biosensor prepared with biocompatible material and carbon nanotube by layer-by-layer self-assembly technique

Prussian Blue (PB) based glucose biosensor was prepared by immobilizing glucose oxidase (GOD) in layer-by-layer (LBL) films with chitosan (Chi) and multi-walled carbon nanotubes (MWNTs). With the increasing of Chi/MWNTs/GOD layers, the response current to glucose was changed regularly and reached a maximum value when the number of layer was six. At the optimized condition, the biosensor exhibits excellent response performance to glucose with a linear range from 1 to 7 mM and a low detection limit of 0.05 mM. The biosensor also shows a high sensitivity of 8.017 μA mM⁻¹ cm⁻², which is attributed to the biocompatible nature of the LBL films. Furthermore, the biosensor shows rapid response, good reproducibility, long-term stability and freedom of interference from other co-existing electroactive species such as ascorbic acid and acetaminophen.     

Amperometric glucose biosensor based on Prussian blue-multiwall carbon nanotubes composite and hollow PtCo nanochains

In this paper, a novel glucose biosensor was developed based on immobilizing glucose oxidase (GOD) on Prussian blue-multiwall carbon nanotubes (PB@MWNTs) composite and hollow PtCo (H-PtCo) nanochains modified electrode. The PB@MWNTs/H-PtCo membrane showed good biocompatibility, large surface-to-volume ratio and excellent electron-conductive ability. The successful fabrication of the PB@MWNTs composite synthesized with MWNTs as a template and Fe(III)-reducer were characterized by UV-vis absorption spectroscopy, Fourier transform infrared (FTIR) spectrometry and transmission electron microscopy (TEM). The hollow PtCo nanochains were also characterized by TEM and X-ray photoelectron spectroscopy (XPS). The response of the biosensor towards glucose under the optimized conditions, as investigated by chronoamperometry, is linear from 3.0 μM to 3.6 mM, with a low detection limit of 0.85 μM (S/N = 3) and a high sensitivity 21 mA M⁻¹ cm⁻². Moreover, the biosensor exhibits strong anti-interferent ability, good reproducibility and excellent stability.     

Effect of temperature-controlled poly(diallyldimethylammonium chloride) on morphology of self-assembled Prussian Blue electrode and its high detection sensitivity of hydrogen peroxide

Based on positively charged poly(diallyldimethylammonium chloride) (PDDA) layer providing nucleation sites for the growth of PB via self-assemble process, regular Prussian Blue (PB) nanocubes was obtained on the Pt electrode by simply adjusting adsorption temperatures of PDDA. Electrochemical impedance spectroscopy (EIS) was applied to study the coverage and electrical resistance of PDDA on the electrode with different adsorbed temperatures. The evolutions of PB morphology with temperature-controlled PDDA were characterized by field emission scanning electron microscope (FESEM). Investigation on the electrochemical property of the modified electrodes was also carried out using Chronoamperometry. Control of temperature could optimize the charge density distribution of PDDA on electrode and further construct the regular growth of PB crystal. At the PDDA adsorbed temperature of 30 °C, the as-fabricated PB modified electrode showed an excellent sensitivity to hydrogen peroxide response of about 1179.6 mA M⁻¹ cm⁻², a rapid response time within 2 s, and a wide linear range up to 600 μM H₂O₂. In addition, the sensor exhibited good reproducibility and stability.     

Flow injection amperometric determination of pyridoxine at a Prussian blue nanoparticle-modified carbon ceramic electrode

This work describes the electrocatalytic properties of a carbon composite electrode (CCE) modified with Prussian blue (PB) nanoparticles (NPs) for the electrocatalytic oxidation of pyridoxine (PN). The morphology of the PBNP-modified CCE was characterized by scanning electron microscopy (SEM). The mechanism and kinetics of the catalytic oxidation reaction of PN were monitored by cyclic voltammetry and chronoamperometry. The rate-limiting step of the charge transfer reaction was found to be a one-electron abstraction. The value of α, k, and D were calculated as 0.66, 6.7 × 10⁴ M⁻¹ s⁻¹, and 1.88 × 10⁻⁵ cm² s⁻¹, respectively. The modified electrode showed electrocatalytic activity toward the oxidation of PN and was used as an amperometric sensor. The sensor exhibited good linear response for PN over the concentration ranges 5-69 and 1-80 μM with detection limits of 0.51 and 0.87 μM, and sensitivities of 0.97 and 0.673 A M⁻¹ cm⁻² in batch and flow conditions, respectively. Some important advantages such as simple preparation, fast response, good stability, and reproducibility of the sensor for the amperometric determination of PN were achieved.     

A novel hydrogen peroxide biosensor based on Au-graphene-HRP-chitosan biocomposites

Graphene was prepared successfully by introducing -SO₃⁻ to separate the individual sheets. TEM, EDS and Raman spectroscopy were utilized to characterize the morphology and composition of graphene oxide and graphene. To construct the H₂O₂ biosensor, graphene and horseradish peroxidase (HRP) were co-immobilized into biocompatible polymer chitosan (CS), then a glassy carbon electrode (GCE) was modified by the biocomposite, followed by electrodeposition of Au nanoparticles on the surface to fabricate Au/graphene/HRP/CS/GCE. Cyclic voltammetry demonstrated that the direct electron transfer of HRP was realized, and the biosensor had an excellent performance in terms of electrocatalytic reduction towards H₂O₂. The biosensor showed high sensitivity and fast response upon the addition of H₂O₂, under the conditions of pH 6.5, potential −0.3 V. The time to reach the stable-state current was less than 3 s, and the linear range to H₂O₂ was from 5 × 10⁻⁶ M to 5.13 × 10⁻³ M with a detection limit of 1.7 × 10⁻⁶ M (S/N = 3). Moreover, the biosensor exhibited good reproducibility and long-term stability.     

Functionalized single-walled carbon nanotubes/polypyrrole composites for amperometric glucose biosensors

This article reports an amperometric glucose biosensor based on a new type of nanocomposite of polypyrrole (PPY) with p-phenyl sulfonate-functionalized single-walled carbon nanotubes (SWCNTs-PhSO₃⁻). An environmentally friendly functionalization procedure of the SWCNTs in the presence of substituted aniline and an oxidative species was adopted. The nanocomposite-modified electrode exhibited excellent electrocatalytic activities towards the reduction or oxidation of H₂O₂. This feature allowed us to use it as bioplatform on which glucose oxidase (GOx) was immobilized by entrapment in an electropolymerized PPY/SWCNTs-PhSO₃⁻ film for the construction of the glucose biosensor. The amperometric detection of glucose was assayed by applying a constant electrode potential value necessary to oxidize or reduce the enzymatically produced H₂O₂ with minimal interference from the possible coexisting electroactive compounds. With the introduction of a thin film of Prussian blue (PB) at the substrate electrode surface, the PPY/GOx/SWCNTs-PhSO₃⁻/PB system shows synergy between the PB and functionalized SWCNTs which amplifies greatly the electrode sensitivity when operated at low potentials. The biosensor showed good analytical performances in terms of low detection (0.01 mM), high sensitivity (approximately 6 μA mM⁻¹ cm⁻²), and wide linear range (0.02 to 6 mM). In addition, the effects of applied potential, the electroactive interference, and the stability of the biosensor were discussed. The facile procedure of immobilizing GOx used in the present work can promote the development of other oxidase-based biosensors which could have a practical application in clinical, food, and environmental analysis.     

Amperometric glucose biosensor based on immobilization of glucose oxidase in electropolymerized o-aminophenol film at Prussian blue-modified platinum electrode

An amperometric glucose biosensor is developed, based on immobilization of glucose oxidase (GO_X) in an electrochemically polymerized, non-conducting poly(o-aminophenol) (POAP) film at Prussian blue (PB)-modified platinum (Pt) microelectrode. Effects of polymerization cycle number for POAP and PB, applied potential used in the determination, pH value of the detection solution and electroactive compounds on the amperometric response of the sensor were investigated and discussed. The electroactive property and rough surface of PB film result in the improvement of the detection limit and the increase of the maximum response current and sensitivity. The biosensor based on Pt/PB/POAP/GO_X electrode has two times lower detection limit, five times larger maximum current and nine times higher sensitivity than those of the biosensor based on Pt/POAP/GO_X electrode. Additionally, the biosensor shows fast response time, large response current, and good anti-interferent ability for l-ascorbic acid, uric acid and acetaminophen. Excellent reproducibility and stability of biosensor are also observed.     

An electrochemical biosensor based on Nafion-ionic liquid and a myoglobin-modified carbon paste electrode

An electrochemical biosensor was constructed based on the immobilization of myoglobin (Mb) in a composite film of Nafion and hydrophobic ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF₆) for a modified carbon paste electrode (CPE). Direct electrochemistry of Mb in the Nafion-BMIMPF₆/CPE was achieved, confirmed by the appearance of a pair of well-defined redox peaks. The results indicate that Nafion-BMIMPF₆ composite film provided a suitable microenvironment to realize direct electron transfer between Mb and the electrode. The cathodic and anodic peak potentials were located at −0.351 V and −0.263 V (vs. SCE), with the apparent formal potential (Ep) of −0.307 V, which was characteristic of Mb Fe(III)/Fe(II) redox couples. The electrochemical behavior of Mb in the composite film was a surface-controlled quasi-reversible electrode process with one electron transfer and one proton transportation when the scan rate was smaller than 200 mV/s. Mb-modified electrode showed excellent electrocatalytic activity towards the reduction of trichloroacetic acid (TCA) in a linear concentration range from 2.0 × 10⁻⁴ mol/L to 1.1 × 10⁻² mol/L and with a detection limit of 1.6 × 10⁻⁵ mol/L (3σ). The proposed method would be valuable for the construction of a third-generation biosensor with cheap reagents and a simple procedure.     

Functionalized carbon nanotube-bienzyme biocomposite for amperometric sensing

An approach to design a biocomposite bienzyme biosensor with the aim of evaluating its suitability as an amperometric sensor using functionalized multiwalled carbon nanotubes (MWCNTs) is presented. The biosensor is based on a bienzyme-channelling configuration, employing the enzymes glucose oxidase (GOx) and horseradish peroxidase (HRP), which were immobilized with toluidine blue (TB) functionalized MWCNTs. The proposed method demonstrates an easy electron transfer between the immobilized enzymes and the electrode via functionalized MWCNTs in a Nafion matrix. Co-immobilization of GOx and HRP was employed to establish the feasibility of fabricating highly effective bienzyme-based biosensors for low-level glucose determination. Bienzyme immobilized TB functionalized MWCNTs were attached to a glassy carbon electrode, and the electrochemical behavior of the sensor was studied using electrochemical impedance spectroscopy, cyclic voltammetry and chronoamperometry. The excellent electrocatalytic activity of the biocomposite film resulted in the detection of glucose under reduced over potential with a wider range of determination from 1.5 × 10⁻⁸ M to 1.8 × 10⁻³ M and with a detection limit of 3 × 10⁻⁹ M. The sensor showed a short response time (within 2 s), good stability and anti-interferant ability. The proposed biosensor exhibits good analytical performance in terms of repeatability, reproducibility and shelf-life stability.