Geometric parameters optimization of planar interdigitated electrodes for bioimpedance spectroscopy

Abstract

This paper is concerned with a physical model of an interdigitated sensor working in a frequency range from 100 Hz to 10 MHz. A theoretical approach is proposed to optimize the use of the sensor for bioimpedance spectroscopy. The correlation between design parameters and frequency behavior in coplanar impedance sensors are described. CoventorWare  software was used to model the biological medium loaded interdigital sensor in three dimensions to measure its electrical impedance. Complete system simulation by a finite element method (FEM) was used for sensor sensitivity optimization. The influence of geometrical parameters (number of fingers, width of the electrodes) on the impedance spectroscopy of the biological medium was studied. The simulation results are in agreement with the theoretical equations of optimization. Thus, it is possible to design a priori such sensor by taking into account the biological medium of interest that will load the sensor.

Towards a biosensor to monitor the sterilisation efficiency of aseptic filling machines

“…At high frequencies the capacitance resulting from the electrolyte is prevalent. The intermediate range is defined by the resistive characteristics of the electrolyte . In the spectra recorded without electrolyte no differentiation according to the three frequency bands was found.…”

“…The transducer structures usually consist of finger pairs and gaps, on which a material under test, such as microbiological samples, can be immobilised. Simulations have demonstrated that the detection limit of such structures is mainly driven by the number of electrodes, the finger width and the interspacing distance . These simulations and impedance analyses have revealed that the electrode geometry should be comparable to the size of the target organism .…”

A Novel Humidity Sensor Based on the Extension of Thompson and Lampard Theorem

“…Performance comparison of the proposed sensor with the interdigitated resistive and capacitive sensors is shown in Table II. The resistance for interdigitated resistive sensor can be written as [11], [12] …”

Microfluidic based impedance biosensor for pathogens detection in food products

“…This thin layer of particles generates capacitance C dl , while the dielectric capacitance C de represents the overall capacitance of the dielectric medium. Both C dL and R Sol are connected in parallel with the direct capacitive coupling between the electrodes (C Cell ), which depends on the solution dielectric constant and the geometry of the electrodes . The parasitic resistors (R Par ) are generated from the connections and wires of the measuring circuit which is small and can be neglected.…”