Mediatorless, electrochemically driven, redox transformations of T1 (type 1) and T2 copper sites in Trametes hirsuta laccase were studied by cyclic voltammetry and spectroelectrochemical redox titrations using bare gold electrode. DET (direct electron transfer) between the electrode and the enzyme was observed under anaerobic conditions. From analysis of experimental data it is concluded that t...

The redox properties of a monolayer of alkanethiolate-protected gold nanoclusters (MPCs) constructed on a gold slide electrode was studied in 1,2-dichloroethane (DCE) electrolyte solutions. The influence of the electrostatic interaction between attached MPCs and the substrate electrode on the absolute standard redox potential of MPCs was theoretically considered and studied experimentally.

The direct electrochemistry of xanthine oxidase (XOD) was accomplished at a gold electrode modified with single-wall carbon nanotubes (SWNTs). A pair of well-defined redox peaks was obtained for XOD with the reduction peak potential at -0.478 V and a peak potential separation of 28 mV at pH 7.0. Both FT-IR spectra and the dependence of the reduction peak current on the scan rate revealed that X...

dye-sensitized solar cells present promising low-cost alternatives to the conventional silicon (si)-based solar cells. the counter electrode  generally consists of pt deposited onto fto plate. since pt is rare and expensive metal, nanostructured carbonaceous materials have been widely investigated as a promising alternative to replace it. carbon nanotubes  have shown significant properties such...

Acid or base concentrations can be determined by performing an acid-base titration with OHor H+ ions, coulometricaliy generated by the electrolysis of water at a noble metal actuator electrode. This can be done very rapidly if the actuator electrode is in close proximity to an ISFET which is used as the indicator electrode to detect the equivalence point in the titration curve. In order to rest...

The self-discharge of hybrid electrochemical capacitors based on the redox activity of electrolyte additives or grafted species to the electrode material is investigated simultaneously for the cell and each individual electrode. Electrochemical capacitors using a redox-active electrolyte consisting in hydroquinone added to the electrolyte solution and a redox-active electrode based on anthraqui...

A novel electrochemical biosensor was developed to detect gene mutation by using a DNA-mismatch binding protein: MutS from Escherichia coli. The MutS protein was immobilized onto an Au-electrode surface via complex formation between a histidine tag of the MutS protein and a thiol-modified nitrilotriacetic acid chemically adsorbed on the Au-electrode surface. When a target double-stranded DNA ha...

A novel electrochemical biosensor for gene mutation detection was developed using a DNA mismatch recognizing protein MutS from E. coli. The MutS protein was immobilized onto an Au electrode by coordination of His-tag at its C-terminus to vacant sites of Ni(II)-nitrilotriacetato complex attached to the surface of electrode. When a target DNA duplex having a mismatch site was captured by the MutS...

The conditional formal potential, E°′of Methyldopa has been studied by cyclic voltammetry at the surface of activated glassy carbon electrode (AGCE) as the working electrode in different pH phosphate buffered solutions. The experimental Standard redox potential, E°′, of Methyldopa is obtained to be 0.72 mV versus SHE (Standard Hydrogen Electrode). E°′ values have also been calculated with the a...

the electrochemistry of banana tissues on a carbon paste electrode modified with multi-walled carbon nanotubes (mwcnts) is presented. cyclic voltammetry is applied to investigate the direct electrochemistry of banana tissues i.e. a source of polyphenol oxidase (ppo). a redox couple with an anodic and counterpart cathodic peak is obtained. the influence of various parameters such as ph, scan rat...