Prussian Blue-modified Electrode Research Articles

Electrochemical Sensor to Detect Proteinuria Using Peptidases and Glutamate Oxidase Jointly Immobilized on a Prussian Blue-modified Electrode

Electrochemical Sensor to Detect Proteinuria Using Peptidases and Glutamate Oxidase Jointly Immobilized on a Prussian Blue-modified Electrode

Current control by electrode coatings formed by polymerization of dopamine at prussian blue-modified electrodes.

Electrode coating with polydopamine (PDA) is fast becoming a popular surface modification technique. In this study we report the investigation of the use of PDA as electrode coatings with Prussian blue (PB) as an electrode material model. The PB layer was galvanostatically deposited at an Au electrode, followed by PDA coating with the assistance of ammonium persulfate as an oxidant. The thickness of PDA coatings was measured to be ∼60 nm. Electrochemical characterization of the PDA-coated PB electrode revealed that the PDA coatings could stabilize the PB at neutral pH and allow the permeation of hydrogen peroxide (H2O2). Moreover, the PDA coatings were found to effectively exclude the common interfering compounds such as cysteine, ascorbic acid and uric acid, and exhibit selective electrocatalysis towards the electroreduction of H2O2. Accordingly, the PDA-coated PB electrode was applied for determination of H2O2 released from live cells.

Uptake and Electrochemical Ejection of Cesium Ion by a Prussian Blue-modified Electrode

Abstract Prussian blue (FeIII4[FeII(CN)6]3) electrochemically deposited on an indium tin oxide electrode was loaded with cesium ion in a diluted aqueous CsCl solution (ca. 40 ppb) followed by reduction or oxidation. Although reduction of Prussian blue does not increase the capacity of cesium uptake, oxidation of Prussian blue releases the entrapped cesium ion.

Solvent-Independent Electrode Potentials of Solids Undergoing Insertion Electrochemical Reactions: Part III. Experimental Data for Prussian Blue Undergoing Electron Exchange Coupled to Cation Exchange

Prussian blue-modified electrodes immersed in K+-containing solutions can be used to obtain a solvent-independent redox potential system. On the basis of theoretical modeling of diffusion processes occurring under the conditions of voltammetry of immobilized particles, voltammetric and chronoamperometric data can be combined to obtain solvent-independent electrode potentials for the K+-assisted one-electron reduction of Prussian blue to Berlin white. Data for water, MeOH, EtOH, MeCN, DMS, DMF, and NM are provided.

Acetylcholinesterase biosensor based on prussian blue-modified electrode for detecting organophosphorous pesticides

In this study, a novel acetylcholinesterase (AChE) biosensor was developed based on dual-layer membranes (chitosan membrane and prussian blue membrane) modifying glassy carbon electrode (GCE). A chitosan membrane was used for immobilizing AChE through glutaraldehyde cross-linking attachment to recognize pesticides selectively. A prussian blue (PB) membrane was electrodeposited on the surface of GCE to enhance electron transfer. Before the detection, the chitosan enzyme membrane was quickly fixed on the surface of PB/GCE with O-ring to prepare an amperometric AChE-PB/GCE sensor for organophosphorus (OP) pesticides. The electrochemical behaviour of AChE-PB/GCE was studied, and the results showed that the chitosan membrane as carrier can absorb a large amount of enzyme, and PB has a significant synergistic effect towards enzymatic catalysis. As a result of these two important enhancement factors, the proposed biosensor exhibited extreme sensitivity to OP pesticides compared to the other kinds of AChE biosensor. The influences of phosphate buffer pH, substrate concentration, incubation time of pesticide on the response of the fabricated biosensor were investigated. Under optimum conditions, the inhibition rates of these pesticides were proportional to their concentrations in the range of 0.01–10 μg l −1, 0.05–10 μg l −1, 0.03–5 μg l −1, and 0.05–10 μg l −1, respectively. The detection limits were found to be 2.5 ng l −1 for dichlorvos, 15 ng l −1for omethoate, 5 ng l −1 for trichlorfon and 10 ng l −1 for phoxim. Moreover, the biosensor exhibited good reproducibility and stability, and it was suitable for trace detection of OP pesticide residue.

A Prussian blue-based amperometric sensor for the determination of hydrogen peroxide residues in milk

A highly selective, sensitive, fast, and stable amperometric sensor for the determination of hydrogen peroxide residues in aseptic milk is presented. To fabricate this amperometric sensor, a thin film of Prussian blue was first electrodeposited on a glassy carbon electrode and then a Nafion polymer layer was formed on the top. It was found that Nafion film greatly improves the anti-interference ability and the stability of the Prussian blue-modified electrode. Factors that influence the overall analytical performance of the sensor, such as the concentration of Nafion drop and pH value of the electrolyte, were examined. Results show that the prepared sensor possesses efficient electrocatalytic activity towards hydrogen peroxide with the detection limit as low as 0.2 μM and linear range from 0.8 μM to 0.12 mM. The developed sensor was applied to the determination of hydrogen peroxide in milk with satisfactory results.

Preparation of GOD/Sol‐Gel Silica Film on Prussian Blue Modified Electrode for Glucose Biosensor Application

AbstractA novel amperometric glucose biosensor was fabricated by in situ incorporating glucose oxidase (GOD) within the sol‐gel silica film on a Prussian blue (PB) modified electrode. The method is simple and controllable, which combined the merits of in situ immobilizing biomolecules in sol‐gel silica film by electrochemical method and the synergic catalysis effects of PB and GOD molecules. Scanning electron microscopy (SEM) showed that the GOD/sol‐gel silica film was homogeneous with a large number of three‐dimensional nanopores, which not only enhanced mass transport, but also maintained the active configuration of the enzyme molecule and prevented the leakage of enzyme, therefore improved the stability and sensitivity of the biosensor. The fabricated biosensor showed fast response time (10 s), high sensitivity (26.6 mA cm−2 M−1), long‐term stability, good suppression of interference, and linear range of 0.01 mM–5.8 mM with a low detection limit of 0.94 μM for the detection of glucose. In addition, the biosensor was successfully applied to determine glucose in human serum samples.

Development of a Novel Silver Nanoparticles-Enhanced Screen-Printed Amperometric Glucose Biosensor

A disposable glucose biosensor is developed by immobilizing glucose oxidase into silver nanoparticles-doped silica sol-gel and polyvinyl alcohol hybrid film on a Prussian blue-modified screen-printed electrode. The silver nanoparticles-enhanced biosensor shows a linear amperometric response to glucose from 1.25 × 10−5 to 2.56 × 10−3 with a sensitivity of 20.09 mA M−1 cm−2, which is almost double that of the biosensors without silver nanoparticles. The immobilized glucose oxidase retained 91% of its original activity after 30 days of storage in phosphate buffer (pH 6.9; 0.1 M) at 4°C. Blood glucose in a rabbit serum sample was successfully measured with the biosensor.

Flow injection analysis of blood l-lactate by using a Prussian Blue-based biosensor as amperometric detector

An amperometric l-lactate biosensor was fabricated by confining lactate oxidase in a Prussian Blue-modified electrode with a Nafion membrane. The detector was assembled in a flow injection apparatus and operated at −0.1 V. Conditions for optimal electrode response were determined by investigating the influence of the amount of immobilized enzyme, the sample volume, and the flow rate. At the established operational conditions, the biosensor exhibited negligible response from interfering species usually present in biological fluids. The stability of the biosensor was also investigated, and its sensitivity was maintained unchanged at certain experimental conditions. l-Lactate was determined in blood samples, and the influence of physical exercise on the results was clearly evidenced, demonstrating that the proposed amperometric detector is suitable for monitoring changes in the l-lactate levels in biological fluids.

Kinetic characterization of Prussian Blue-modified graphite electrodes for amperometric detection of hydrogen peroxide

Prussian Blue-modified graphite electrodes (G/PB) with electrocatalytic activity toward H2O2 reduction were obtained by PB potentiostatic electrodeposition from a mixture containing 2.5 mm FeCl3 + 2.5 mm K3[Fe(CN)6] + 0.1 m KCl + 0.1 m HCl. From cyclic voltammetric measurements, performed in KCl aqueous solutions of different concentrations (5 × 10−2–1 m), the rate constant for the heterogeneous electron transfer (k s) was estimated by using the Laviron treatment. The highest ks value (10.7 s−1) was found for 1 m KCl solution. The differences between the electrochemical parameters of the voltammetric response, as well as the shift of the formal potential, observed in the presence of Cl− and NO 3 − compared to those observed in the presence of SO 4 2− ions, points to the involvement of anions in the redox reactions of PB. The G/PB electrodes showed a good electrochemical stability proved by a low deactivation rate constant (0.8 × 10−12 mol cm2 s−1). The electrocatalytic efficiency, estimated as the ratio $$(I_{cat})_{H_2 O_2 } /(I_{cat})$$ , was found to be 3.6 (at an applied potential of 0 mV vs. SCE; Γ = 5 × 10−8 mol cm−2) for a H2O2 concentration of 5 mm, thus indicating G/PB electrodes as possible H2O2 sensors.

Dependence of redox characteristics in Prussian blue-modified electrode on pH of electrolytic solution

Redox characteristics in Prussian blue (PB) film were studied from a viewpoint of dependency of apparent diffusion coefficient ( D app) on pH of electrolytic solution. The PB film was electrodeposited on Pt foil in electrolysis bath of FeCl 3 and K 3Fe(CN) 6 mixed solution. Electrolytic solution for measurements was 1.0 mol dm −3 KCl solution with various pH which was adjusted by 0.1 mol dm −3 HCl. Cyclic voltammograms of the PB-modified electrode suggested that redox reactions proceeded by diffusion-controlled mode. Chronoamperometry and chronocoulometry with potential step range between 0.5 and 0.0 V showed that maximum arcs of D app were present at redox reactions in pH 2–3 of electrolytic solution. In order to analyze the D app behavior of the PB film, concentrations of K + ion and Cl − ion were measured by ionchromatography, and configuration of the ions in the soluble PB lattice was discussed. Steric hindrance for K + ion diffusion in the PB film was considered to arise chiefly from interstitial K + ion among K + ion, H + ion, and Cl − ion in the PB lattice.

Investigation of baker’s yeast Saccharomyces cerevisiae- and mediator-based carbon paste electrodes as amperometric biosensors for lactic acid

Carbon paste electrodes modified with baker’s yeast (a source of cytochrome b2) and various mediators (Nile blue, methylene blue, toluidine blue, Meldola blue, p-hydroquinone and Prussian Blue) were tested for the sensitivity to lactic acid. Electrochemical activity of mediators increased when baker’s yeast was added to the paste. Only Meldola blue and Prussian Blue-modified electrodes responded to lactic acid. The operating potentials were +0.1 and +0.3V (versus saturated Ag/AgCl), respectively. A linear range in the dependence of the current response upon the concentration of lactic acid was up to 1mM. Electrode sensitivity and apparent Michaelis constants (KM′) decreased with aging of the yeast.

Construction and analytical characterization of Prussian-Blue-based carbon paste electrodes and their assembly as oxidase enzyme sensors.

This paper reports on the development and characterization of Prussian Blue-modified carbon paste electrodes. New methods of matrix modification with Prussian Blue are reported. Two different carbon pastes have been prepared, using mineral oil or solid paraffin, thus obtaining different types of sensors whose behavior toward the electrochemical reduction of hydrogen peroxide has been fully characterized. Results obtained with Prussian Blue-modified electrodes showed a long operational lifetime, an excellent stability in a wide range of pH (3-9), a high sensitivity, and a fast response time. In addition, the coupling of solid carbon paste modified with Prussian Blue and the enzymes glucose oxidase and choline oxidase led to the assembling of biosensors that showed an optimum working range at alkaline pH.

Electroanalytical applications of Prussian Blue and its analogs

The applications of transition metal hexacyanoferrates in electroanalysis are surveyed. Prussian Blue (ferric hexacyanoferrate) is recognized as the most promising low-potential transducer for hydrogen peroxide reduction among all known systems. The advantages of Prussian Blue over platinum or peroxidase electrodes for hydrogen peroxide detection are discussed. Various types of biosensors based on transition metal hexacyanoferrates and oxidase enzymes are considered. Amperometric biosensors based on Prussian Blue-modified electrodes allow the detection of glucose and glutamate down to 10–7 mol L–1 in the flow-injection mode. The future prospects of Prussian Blue-modified electrodes in analytical chemistry for the monitoring of chemical toxic agents, in clinical diagnostics, and in food control are outlined.

Sensor for Hydrogen Peroxide Based on Prussian Blue Modified Electrode: Improvement of the Operational Stability

Improvement of the operational stability of amperometric sensors based on Prussian Blue (PB) modified glassy carbon electrodes is presented. The long term performance of the sensors was evaluated by injection of hydrogen peroxide (5 µM in potassium buffer) solutions in a flow-injection system during a period of 5 ‐10 h. The following parameters were investigated and correlated with the performance of the sensor: the times for electrodeposition and electrochemical activation, temperature, storage time, pH, composition of the buffer solution and of volume sample injected. These analytical characteristics of the modified electrode can be emphasized: initial sensitivity of 0.3 A cm ‐2 M ‐1 , detection limit of ca. 0.5 µM, precise results (r.s.d.< 1.5%) and possibility to carry out around 50 samples (50 µL) per hour.

Glucose biosensor based on glucose oxidase immobilized in electropolymerized polypyrrole and poly( o-phenylenediamine) films on a Prussian Blue-modified electrode

Glucose oxidase (GOD) was immobilized in either a layer of polypyrrole (PPY) or poly( o-phenylenediamine) (POPD) by electropolymerization of the corresponding monomer on platinum electrode modified by Prussian Blue (PB). The resulting biosensors showed amperometric responses to glucose due to the detection of hydrogen peroxide formed during the enzymatic reaction and could be operated by both in an anodic manner at a potential of 0.6 V vs. Ag/AgCl, or a cathodic manner at 0.0 or 0.2 V. In the case of POPD-modified electrode, the influence of interferents like ascorbate or acetaminophen could be reduced drastically.

Amperometric biosensor for glutamate using prussian blue-based "artificial peroxidase" as a transducer for hydrogen peroxide.

The specially deposited Prussian Blue denoted as "artificial peroxidase" was used as a transducer for hydrogen peroxide. The electrocatalyst was stable, highly active, and selective to hydrogen peroxide reduction in the presence of oxygen, which allowed sensing of H2O2 around 0.0 V (Ag/AgCl). Glutamate oxidase was immobilized on the surface of the Prussian Blue-modified electrode in a Nafion layer using a nonaqueous enzymology approach. The calibration range for glutamate in flow injection system was 1 x 10(-7)-1 x 10(-4) M. The lowest concentration of glutamate detected (1 x 10(-7) M) and the highest sensitivity in the linear range of 0.21 A M-1 cm-2 were achieved. The influence of reductants was practically avoided using the low potential of an indicator electrode (0.0 V Ag/AgCl). The attractive performance characteristics of the glutamate biosensor illustrate the advantages of Prussian Blue-based "artificial peroxidase" as transducer for hydrogen peroxide detection.

Prussian Blue-Based First-Generation Biosensor. A Sensitive Amperometric Electrode for Glucose

A first-generation amperometric glucose biosensor based on a Prussian Blue-modified electrode was developed. Prussian Blue was found to be a better electrocatalyst for hydrogen peroxide reduction than platinum. H 2 O 2 was detected at the Prussian Blue-modified electrode in the presence of oxygen by both electrooxidation and electroreduction. The glucose amperometric biosensor was made by glucose oxidase immobilization onto a Prussian Blue-modified electrode with a Nafion layer. The biosensor response exhibited a linear dependence on analyte concentration in the range 1 x 10 -6 -5 x 10 -3 M. The cathodic current density after addition of 10 -6 M glucose was 0.18 μA/ cm 2 . When hydrogen peroxide produced via the enzyme reaction was detected by electroreduction, the biosensor response was independent of reductants. This amperometric biosensor is expected to obey the requirements for noninvasive diagnostics.

Electroreduction of CO 2 to C 2 and C 3 compounds on Bis(4,5-dihydroxybenzene-1,3-disulphonato)ferrate(II)-fixed polyaniline | Prussian Blue-modified electrode in aqueous solutions

Electrocatalytic reduction of CO 2 has been performed using the bis(1,2-dihydroxybenzene-3,5-disulphonato)ferrate(II)-immobilized polyaniline | Prussian Blue-modified electrode in aqueous solutions. CO 2 was reduced at a low overpotential under ambient condition, and lactic acid, together with C 2 and C 1 compounds, was obtained with the highest selectivity of about 88%. The most probable pathway of the reduction of CO 2 is the stepwise hydrogenation by H ads. Adsorbed hydrogen atoms were generated by the catalytic reduction of H + ions near the PAn | PB interface where the doping and undoping processes of K + ions proceed simultaneously.