Electron-transfer biosensors.

The electrochemistry of redox proteins is now well established. Conditions exist which allow electron-transfer reactions of all simple proteins to proceed rapidly and reversibly at electrodes. Coupling of the electrode reaction to enzymes, for which the redox proteins act as cofactors, allows exploitation of this good electrochemistry. This is well illustrated by the enzyme-catalysed electrochemical oxidation of p-cresol to p-hydroxybenzaldehyde, which has been shown to proceed along with coupling to the electrode via the copper protein, azurin, or the organometallic compound ferroceneboronic acid. Ferrocene derivatives, in general, show a degree of versatility, coupling the electron-transfer reactions of many enzymes. Thus derivatives of the ferricinium ion act as excellent electron-transfer reagents from the enzyme glucose oxidase. The system is capable of detecting glucose in blood. Similar procedures, in conjunction with the appropriate enzyme, have yielded assays for, among others, H2O2 and cholesterol.

[1]  F. Scheller,et al.  Studies on electron transfer between mercury electrode and hemoprotein. , 1975, Biochimica et biophysica acta.

[2]  B. Zak.  Cholesterol methodologies: a review. , 1977, Clinical chemistry.

[3]  Nicholas J. Walton,et al.  Surface modifiers for the promotion of direct electrochemistry of cytochrome c , 1984 .

[4]  J. Ziegenhorn,et al.  Reagent for the enzymatic determination of serum total cholesterol with improved lipolytic efficiency. , 1983, Clinical chemistry.

[5]  H. Hill,et al.  A method for estimation of hydrogen peroxide based on mediated electron transfer reactions of peroxidases at electrodes , 1986 .

[6]  F. Armstrong,et al.  Direct electrochemistry of the photosynthetic blue copper protein plastocyanin. Electrostatic promotion of rapid charge transfer at an edge-oriented pyrolytic graphite electrode , 1985 .

[7]  H. Hill,et al.  Novel method for the investigation of the electrochemistry of metalloproteins: cytochrome c , 1977 .

[8]  A. Turner,et al.  Ferrocene-mediated enzyme electrode for amperometric determination of glucose. , 1984, Analytical chemistry.

[9]  N. Lewis,et al.  Electrochemical reduction of horse heart ferricytochrome c at chemically derivatized electrodes. , 1981, Science.

[10]  H. Hill,et al.  Homogeneous ferrocene-mediated amperometric immunoassay. , 1986, Analytical chemistry.

[11]  H. Hill,et al.  Amperometric enzyme electrodes , 1986 .

[12]  F. Armstrong,et al.  Surface selectivity in the direct electrochemistry of redox proteins. Contrasting behaviour at edge and basal planes of graphite , 1984 .

[13]  M. Harmer,et al.  The direct electrochemistry of redox proteins at metal oxide electrodes , 1985 .

[14]  C. Olson,et al.  Amperometric enzymatic determination of total cholesterol in human serum with tubular carbon electrodes. , 1979, Analytical chemistry.

[15]  F. Armstrong,et al.  Direct electrochemical reduction of ferredoxin promoted by Mg2+ , 1982 .

[16]  R. V. Duyne,et al.  Surface-enhanced resonance Raman scattering from cytochrome c and myoglobin adsorbed on a silver electrode , 1980 .

[17]  M. Klapper,et al.  Electrochemical studies of heme proteins. Coulometric, polarographic, and combined spectroelectrochemical methods for reduction of the heme prosthetic group in cytochrome c. , 1972, Journal of the American Chemical Society.

[18]  A. Cass,et al.  Ferricinium ion as an electron acceptor for oxido-reductases , 1985 .

[19]  W. Heineman,et al.  Measurement of enzyme E'values by optically transparent thin layer electrochemical cells. , 1975, Analytical chemistry.