An improved polarographic multiwire surface PO2 electrode, particularly for measurement of high PO2 values.

Abstract

In 1956 Clark described a Polarographic electrode which allowed to measure the Po2, particularly in biological materials with an exactitude and stability which hitherto was not possible. This was achieved by a membrane which separated electrode and biological material from each other so that the Polarographic reaction at the Pt surface and the current transfer at the reference electrode took place in a stable environment. However, our own experiments had shown (Lübbers et al., 1969) that at high Po2 values even Clark type electrodes with an Ag/AgCl reference electrode and a buffered 0.1 mol KCl solution may drift so much that longer lasting experiments are impossible. Since we wanted to measure the Po2 histogram of the guinea pig brain perfused with a blood-free perfused medium (Heinrich et al., this volume) which was equilibrated with carbogen (95% O2 and 5% CO2), we investigated possibilities to improve the stability of the electrode, particularly at high Po2 values.KeywordsSilver OxideOxide ElectrodeCurrent TransferTeflon MembraneClark Type ElectrodeThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.