The present work describes the construction of a new modified electrode by casting the appropriate mixture of a metallocene, which has been introduced in the experimental part, as a mediator at the surface of glassy carbon (GC) electrode. The proposed modified GC electrode was used for the determination of ascorbic acid (AA) in phosphate buffer (PB) solution (pH = 4.0). When compared to bare GC...

A method is described for the rapid sequential measurement of Na, Cl-, and Hactivities on the skin surface with ion-selective electrodes. Rationales are given for details of technique such as temperature control, use of a conducting bridge, pH-dependence of sodium electrode performance, and the uniform electrode setting for all tests. Data on reproducibility document the precision of the method...

Rhodes, Apsimon, and Lawrie (1966) have recently measured pH in the duodenal bulb for long periodsl* using two glass electrodes. By this method it is possible to maintain the distal electrode within the duodenal bulb for long periods but its exact position in the bulb cannot be determined. Over short _.... periods of time, however, the electrode can be located accurately by radiological methods...

The Cyclic Voltammetric behaviour of copper(II)tetramethylethylenediamine systems with [Cu(II)]:[tmen]=1:10, 1:100 molar ratios, 1×10M Cu(ClO4)2.6H2O in aqueous 0.2M NaClO4 supporting electrolyte have been studied at pH5.0,6.50 7.20,9.10, 10.30, 10.85 and 11.20. The electrode process show quasi reversible one electron charge transfer preceded and followed by chemical reaction at glassy carbon e...

A highly selective PVC membrane electrode based on a cerium-salen complex was prepared. The sensor displays an anti-Hofmeister selectivity sequence with a preference for iodide ion over many common organic and inorganic anions. The proposed electrode exhibits a near-Nernstian behavior over a wide concentration range (5.0 x 10(-2) - 8.0 x 10(-6) M) with a slope of 57.5 mV per decade, and a detec...

A biosensor for the specific determination of uric acid in urine was developed using urate oxidase (EC 1.7.3.3) in combination with a dissolved oxygen probe. Urate oxidase was immobilized with gelatin by means of glutaraldehyde and fixed on a pretreated teflon membrane to serve as enzyme electrode. The electrode response was maximum when 50 mM glycine buffer was used at pH 9.2 and 35 degrees C....

Aryl-substituted tetraimine complexes related to Co(dmgBF(2))(2)(MeCN)(2) (dmg = dimethylglyoxime) were synthesized and are active for hydrogen evolution. Co(dmgBF(2))(2)(MeCN)(2) can be adsorbed to a glassy carbon electrode. The chemically modified electrode is active for hydrogen evolution in aqueous solution at pH < 4.5, with an overpotential of only 100 mV.

fabrication and electrochemical characterization of a sensor for the determination of epinephrine (ep), uric acid (ua) and folic acid (fa) is described. the sensor  was prepared using carbon paste electrode (cpe) modified with 3,4-dihydroxybenzaldehyde-2,4-dinitrophenylhydrazone (ddp) and carbon nanotubes (cnts), which makes the modified electrode highly sensitive for the electrochemical detect...

The experiments were carried out in an electro coagulation reactor with aluminum as sacrificial electrodes. The influence of electrolysis time, current density, pH, NaCl concentration, rotational speed of the stirrer and electrode distance on reduction of color, COD and BOD were studied in detail. From the experimental results, 25mA/cm2 current density, pH of 7, 1 g/l NaCl, 100 rpm, 28 ◦C tempe...

Graphene nanoflakes (GNF) of diameter ca. 30 nm and edge-terminated with carboxylic acid (COOH) or amide functionalities were characterised electrochemically after drop-coating onto a boron-doped diamond (BDD) electrode. In the presence of the outer-sphere redox probe ferrocenemethanol there was no discernible difference in electrochemical response between the clean BDD and GNF-modified electro...