A Working Equation for Oxygen Sensing Disk Electrodes

Abstract

For more than 35 years, noble metal electrodes have been employed to measure oxygen partial pressure in biological fluids and other media. Anyone who has attempted to use these types of electrodes is well aware of the instability and drift attendant to them. While a great deal of material can be found in the electrochemical and analytical chemical literature regarding the catalytic interaction of noble metal surfaces with oxygen, this literature usually pertains to large surfaces, non isotonic media and/or rotating ring-disc systems. Comparatively little has been published concerning the interaction between oxygen and noble metal surfaces for electrode sizes employed in biological applications.