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A philosophy for electrochemical impedance spectroscopy is presented which integrates experimental observation, model development, and error analysis. This approach is differentiated from the usual sequential model development for given impedance spectra by its emphasis on obtaining supporting observations to guide model selection, use of error analysis to(More)
The objective of this study was to quantitatively compare measurements of tritiated water permeability with impedance determined at either 100 or 1000 Hz using an LCR databridge on the same pieces of skin. A previously published expression based on a simple circuit of a parallel resistor and constant phase element (CPE) was used to relate (RPARA) measured(More)
Bode plots, corrected for Ohmic resistance, logarithmic plots of the imaginary component of the impedance, and effective capacitance plots are shown to be useful complements to the more traditionally used complex-plane and Bode representations for electrochemical impedance data. The graphical methods are illustrated by synthetic data and by experimental(More)
Testing whether the barrier of skin samples has sufficient integrity for meaningful measurements of in-vitro chemical permeability is usually required when data are generated for regulatory purposes. Recently, skin integrity has been assessed using LCR databridge measurements, which are reported as resistances determined in either series (SER) or parallel(More)
Electrochemical impedance spectroscopy is a convenient method that has been used to characterize skin barrier function, which affects drug delivery into and through the skin. The objective of this study was to relate changes in skin barrier function arising from mechanical damage to changes in the impedance spectra. These observations are compared in a(More)
To relate changes in the electrochemical impedance spectra to the progression and mechanism of skin damage arising from exposure to dimethyl sulfoxide (DMSO). Electrochemical impedance spectra measured before and after human cadaver skin was treated with neat DMSO or phosphate buffered saline (control) for 1 h or less were compared with electrical circuit(More)
In neuroprosthetic applications, long-term electrode viability is necessary for robust recording of the activity of neural populations used for generating communication and control signals. The corrosion of tungsten microwire electrodes used for intracortical recording applications was analyzed in a controlled bench-top study and compared to the corrosion(More)
The use of the Kramers-Kronig (KK) relations to evaluate the consistency of impedance data has been limited by the fact that the experimental frequency domain is necessarily finite. Current algorithms do not distinguish between the residual errors caused by a frequency domain that is too narrow and discrepancies caused by a system which does not satisfy the(More)
Dye-sensitized solar cells (DSSCs) based on ordered photoanode morphologies, such as nanotubes and nanowires, are widely gaining attention because these geometries are believed to enhance interfacial charge transfer and bulk charge transport. Unfortunately, experimental results have yet to show substantial improvement to conversion efficiency over(More)