Electrodes Prussian blue modified

Tan, X.C.,Tian, Y.X., Cai, P.X. andZou, X.Y. (2005) Glucose biosensor based on glucose oxidase immobilized in sol—gel chitosan/silica hybrid composite film on Prussian blue modified glass carbon electrode. Analytical and Bioanalytical Chemistry, 381, 500-507. 

Non-conductive polymers on the surface of Prussian blue modified electrodes... 

A cyclic voltammogram of a Prussian blue-modified electrode is shown in Fig. 13.2. In between the observed two sets of peaks the oxidation state, which is correspondent to the Prussian blue itself, occurs. Its reduction is accompanied with loss of... 

FIGURE 13.2 Typical cyclic voltammogram of Prussian blue-modified smooth (mirrored glassy carbon) electrode 0.1 M KC1, 40mV s 1. 

Electrocatalysis in oxidation has apparently first been shown for ascorbic acid oxidation by Prussian blue [60] and later by nickel hexacyanoferrate [61]. More valuable for analytical applications was the discovery in the early 1990s of the oxidation of sulfite [62] and thiosulfate [18, 63] at nickel [62, 63] and also ferric, indium, and cobalt [18] hexacyanoferrates. More recently electrocatalytic activity in thiosulfate oxidation was shown also for zinc [23] hexacyanoferrate. Prussian blue-modified electrodes allowed sulfite determination in wine products [64], which is important for the wine industry. 

In contrast to a variety of oxidizable compounds, only a few examples for the detection of strong oxidants with transition metal hexacyanoferrates were shown. Among them, hydrogen peroxide is discussed in the following section. Except for H202, the reduction of carbon dioxide [91] and persulfate [92] by Prussian blue-modified electrode was shown. The detection of the latter is important in cosmetics. It should be noted that the reduction of Prussian blue to Prussian white occurs at the lowest redox potential as can be found in transition metal hexacyanoferrates. 

FIGURE 13.3 Hydrodynamic voltammograms of Prussian blue-modified electrodes in a wall-jet cell with continuous flow of 0.8ml/min ( ) background in air saturated solution (0.1 M KC1 + 0.01 M phosphate, pH 6.0), ( ) 0.1 mM H2O2. 

In contrast to metal surfaces, the growth of non-conducting polymers on the top surface of Prussian blue-modified electrodes can be independently monitored due to... 

The analytical performance of Prussian blue-modified electrodes in hydrogen peroxide detection were investigated in a flow-injection system equipped with a wall-jet cell. Nano-structured Prussian blue-modified electrodes demonstrate a significantly decreased background, which results in improved signal-to-noise ratio. 

Application of transition metal hexacyanoferrates for development of biosensors was first announced by our group in 1994 [118]. The goal was to substitute platinum as the most commonly used hydrogen peroxide transducer for Prussian blue-modified electrode. The enzyme glucose oxidase was immobilized on the top of the transducer in the polymer (Nation) membrane. The resulting biosensor showed advantageous characteristics of both sensitivity and selectivity in the presence of commonly tested reductants, such as ascorbate and paracetamol. 

J.M. Zen, P.Y. Chen, and A.S. Kumar, Flow injection analysis of an ultratrace amount of arsenite using a Prussian blue-modified screen-printed electrode. Anal. Chem. 75, 6017-6022 (2003). 

P.N. Deepa and S.S. Narayanan, Sol-gel coated Prussian blue modified electrode for electrocatalytic oxidation and amperometric determination of thiols. Bull. Electrochem. 17, 259-264 (2001). 

F. Ricci, F. Arduini, A. Amine, D. Moscone, and G. Palleschi, Characterisation of Prussian blue modified screen-printed electrodes for thiol detection. J. Electroanal. Chem. 563, 229—237 (2004). 

U. Scharf and E.W. Grabner, Electrocatalytic oxidation of hydrazine at a Prussian Blue-modified glassy carbon electrode. Electrochim. Acta 41, 233-239 (1996). 

A.A. Karyakin, E.E. Karyakina, and L. Gorton, On the mechanism of H202 reduction at Prussian blue modified electrodes. Electrochem. Commun. 1, 78-82 (1999). 

I.L. Mattos, L. Gorton, T. Ruzgas, and A.A. Karyakin, Sensor for hydrogen peroxide based on Prussian blue modified electrode improvement of the operational stability. Anal. Sci. 16, 1-5 (2000). 

A.A. Karyakin, O.V. Gitelmacher, and E.E. Karyakina, A high-sensitive glucose amperometric biosensor based on Prussian blue modified electrodes. Anal. Lett. 11, 2861—2869 (1994). 

L.V. Lukachova, E.A. Kotel nikova, D. D Ottavi, E.A. Shkerin, E.E. Karyakina, D. Moscone, G. Palleschi, A. Curulli, and A.A. Karyakin, Electrosynthesis of poly-o-diaminobenzene on the Prussian Blue modified electrodes for improvement of hydrogen peroxide transducer characteristics. Bioelectrochemistry 55, 145-148 (2002). 

X. Zhang, J. Wang, B. Ogorevc, and U.E. Spichiger, Glucose nanosensor based on Prussian-blue modified carbon-fiber cone nanoelectrode and an integrated reference electrode. Electroanalysis 11, 945-949 (1999). 

J.P. Li, T.Z. Peng, and Y.Q. Peng, A cholesterol biosensor based on entrapment of cholesterol oxidase in a silicic sol-gel matrix at a Prussian blue modified electrode. Electroanalysis 15, 1031—1037 (2003). 

B. Haghighi, S. Varma, F.M. Alizadeh, Y. Yigzaw, and L. Gorton, Prussian blue modified glassy carbon electrodes - study on operational stability and its application as a sucrose biosensor. Talanta 64, 3-12 (2004). 

Q. Deng, B. Li, and S. Dong, Self-gelatinizable copolymer immobilized glucose biosensor based on Prussian Blue modified graphite electrode. Analyst 123, 1995-1999 (1998). 

F. Ricci and G. Palleschi, Sensor and biosensor preparation, optimisation and applications of Prussian Blue modified electrodes, Biosens. Bioelectron., 21 (2005) 389-407. 

Prussian blue modified screen-printed electrodes as sensitive and stable probes for H202 and thiol measurements... 

Stability of Prussian blue modified screen-printed electrodes The operational stability of all the PB-modified sensors is a critical point, especially at neutral and alkaline pH. A possible explanation for reduced stability could be the presence of hydroxyl ions at the electrode surface as a product of the H202 reduction. Hydroxyl ions are known to be able to break the Fe-CN-Fe bond, hence solubilising the PB [21]. An increased stability of PB at alkaline pH was first observed by our group after adopting a chemical deposition method for the modification of graphite particles with PB for the assembling of carbon paste electrodes [48]. 

Scheme 1. Schematic representation of the system adopted for glucose and pesticide detection. In the upper part of the scheme is shown the reaction chain for the detection of acetylthiocholine giving a measure of acetylcholinesterase (AChE) activity which can be related to pesticide content. In the lower part of the scheme is shown the classic reaction utilised in the case of an oxidase enzyme (glucose oxidase—GOx) for the detection of glucose. In the first case, the final product is thiocholine and in the second, H202, both are measured at the Prussian blue modified electrode at an applied potential of 0.2 V vs. Ag/AgCl and —0.05 V vs. Ag/AgCl, respectively.

K. Itaya, N. Shoji and I. Uchida, Catalysis of the reduction of molecular oxygen to water at Prussian blue modified electrodes, J. Am. Chem. Soc., 106 (1984) 3423-3429. 

K. Itaya, H. Akahoshi and S. Toshima, Electrochemistry of Prussian blue modified electrodes an electrochemical preparation method, J. Electroc-hem. Soc., 129(7) (1982) 1498-1500. 

R. Garjonyte and A. Malinauskas, Glucose biosensor based on glucose oxidase immobilized in electropolymerized polypyrrole and poly(o-phe-nylenediammine) films on a Prussian blue-modified electrode, Sens. Actuators B, 63 (2000) 122-128. 

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