We performed numerical simulations on an extremely fast, mediated, electron transfer-type bioelectrocatalytic reaction using a microband electrode. The simulations under fast-enzyme-kinetics conditions predicted that the decrement of the current density by increaseing the microband thickness would effectively improve the upper limit of detection. These predictions were accurate for an ultrathin...

Gold is determined in aqueous gold-containing drug solutions, 8 X 108 to 1 X 10 mol/liter, and in such drugs in serum, 2 X 106 to 1 X 10 mol/ liter, by electrodeposition onto a carbon paste electrode at -0.3 V vs. a saturated calomel electrode and subsequent stripping at constant current. Aqueous solutions are prepared for electrodeposition with a ceric perchlorate-hydrogen peroxide treatment. ...

Thin-film gold electrodes were produced by radio-frequency sputtering using a polyvinyl chloride foil as substrate. The voltammetric behavior was characterized in various electrolyte solutions. In alkaline and neutral aqueous solutions reliable voltammetric measurements can be performed while in acidic media some nondefined phenomena occur. A novel type of electrode for batch injection analysis...

Polarization modulation-Fourier transform infrared (PM-FTir) spectra were. obtained in situ for polymer films of neutral red and thionine, and for a lilm of leucomethylene blue generated on a gold electrode as a function of potential. The spectra of the polymer films revealed that the aromatic rings lie mostly parallel to the electrode surface in both the reduced and oxidized forms. In contrast...

We describe the electrogenerated chemiluminescence (ECL) processes of the Ru(bpy)3(2+) (bpy = 2,2'-bipyridyl)/ tripropylamine (TPrA) system at glassy carbon, platinum, and gold electrodes. The electrochemical behavior of TPrA on different electrode materials and its influence on the ECL process are demonstrated. At glassy carbon electrodes, the direct oxidation of TPrA began at approximately 0....

An electrochemical aptasensor for detection of trace amounts of aflatoxin M1 was developed. This required immobilization of aptamer on screen printed gold electrode comprising of working electrode, counter electrode and reference electrode and was achieved by sequentially layering dithiodipropionic acid, streptavidin and biotinylated-tetraethylene glycol-aptamer. Immobilization of aptamer was m...

Qualitative defects and resistances in 94 used gold foil electrodes were examined. The electrodes were divided into four groups of varying resistances and gold coating defects. Ten were randomly selected from each group to measure standard photopic electroretinograms (ERGs) in a normal subject. Ten new electrodes were used as controls. There was no significant difference among the electrode gro...

This study introduces two new processes that highly enable PEDOT:PSS (poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)) as stable coating material for chronic neural stimulation. In first process, strong mechanical bonding between PEDOT:PSS coating and gold electrodes is achieved by creating rough porous surface with partial iodine etching. PEDOT:PSS coating on iodine etched gold electro...

A voltammetric electronic tongue consisting of a composite metal base electrode array for discrimination of basic taste has been presented. The electrode array consisting of Gold, Nickel, Palladium, Copper and Glassy Carbon as working electrode, has been used for transforming information of taste substances into electric signal. The electrodes output show different patterns for chemical substan...

A monolayer of Nile Blue (NB) has been covalently immobilized on the self-assembled thiol-monolayer modified gold electrode. Cyclic voltammograms indicated a stable and reverse redox process of NB bonded on the electrode surface. The mechanisms of redox process coupling with proton transfer were proposed. The NB-modified electrode showed excellent electrocatalytic activity toward Nicotinamide a...