Accession Number : ADA265208
Title : Characterization of Small Noble Metal Electrodes by Voltammetry and Energy Dispersive X-Ray Analysis
Descriptive Note : Technical rept.
Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF CHEMISTRY
Personal Author(s) : Strein, Timothy G ; Ewing, Andrew G
Report Date : 26 Jan 1993
Pagination or Media Count : 34
Abstract : Construction and characterization of platinum and gold electrodes with total structural diameters of 1-2 micrometers is described. These small voltammetric probes have been constructed by direct electroreduction of noble metals onto the tips of etched carbon fiber microdisk electrodes. Voltammetry, electron microscopy, energy-dispersive x-ray analysis, and pulsed amperometric detection have been used to characterize these electrodes. Dopamine concentrations have been determined over a range of 10(exp -4) to 10(exp -3) M in the biological buffer system which contains 25 mM glucose, a compound known to adsorb strongly to electrodes. Amperometric monitoring at a constant potential with these small results in signal decay of 20% to 40% in a ten minute experiment. Pulsed amperometric detection minimizes electrode fouling, resulting in 5% or less signal decay over the same ten minute period.
Descriptors : *ENERGY , *X RAYS , *PLATINUM , *ELECTRODES , *GOLD , *DISPERSIONS , *VOLTAMMETRY , BUFFERS , METALS , DIAMETERS , CARBON FIBERS , GLUCOSE , DOPAMINE , CONSTRUCTION , PULSES , ELECTRON MICROSCOPY , ETCHING , PROBES , DETECTION , BIOLOGY
Subject Categories : Inorganic Chemistry
Electricity and Magnetism
Atomic and Molecular Physics and Spectroscopy
Distribution Statement : APPROVED FOR PUBLIC RELEASE