Simultaneous determination of oxygen transport characteristics of six membranes by hexagonal dissolved oxygen sensor system

A Bipartite Expression for the Transient Amperometric Current at a Membrane Covered Planar Electrode to Characterize Solute Diffusion Through the Membrane

“…The time lag error itself consists of two parts, the time lag calculation from curve fitting and the experimental determination of start time. Whilst curve fitting in a time lag calculation would be reasonably accurate, the error in start time determination would be more serious and errors have been observed between experimental curves and simulated ones [10]. Thus, computed curves started earlier than the experimental curves, i.e., the time lag value overestimated the actual value.…”

“…Kim et al [10] approaches À 1 and so also fails. Experimentally, for T approaching infinity, the normalized current approaches 1, but this then leads to Equations 7 and 8 tending to zero so these equations fail as well.…”

“…McBreen et al [5] proposed a planar electrode for the amperometric detection of hydrogen through a metal membrane forty years ago, and more recently, Kimble et al [7] estimated the diffusion coefficient of hydrogen through a propriety ion exchange membrane. Tarnowski et al [8] were similarly able to characterize oxygen transport at a refunctionalized fluoropolymeric membrane; Compañ et al [9,11] characterized oxygen diffusion through silicone and hydrogel membranes; Kim et al [10] determined oxygen transport through a fluorinated ethylene propylene membrane.…”

“…None of the above expressions, except the bipartite expression, thus offer a description for dynamic response over the entire time range. Whilst the simple time lag method is reasonably accurate [10], indeed perfect fit with experiment is claimed, there remains method-dependent disparity between experimental and simulated currents.…”

Designing Sensitivity: A Comparative Analysis of Microelectrode Topologies for Electrochemical Oxygen Sensing in Biomedical Applications

“…The Clark-type electrode-a popular electrochemical sensor design-presents a trielectrode system covered by a semi-permeable membrane and an electrolytic layer that exploits reduction-oxidation reactions to generate current readings that correspond to analyte concentrations. In the case of oxygen, the working electrode provides the reaction site for the reduction of dissolved oxygen with the surrounding water molecules [6]. The reference electrode follows a separate voltage biasing scheme and serves to stabilize the potential of the electrochemical system in solution [7,8].…”