DETERMINATION OF FARADAY IMPEDANCE PARAMETERS TO INCREASE ACCURACY IN CONDUCTOMETRY AND OBTAIN ADDITIONAL DATA

Abstract

A simple algorithm for determining the set of parameters of the equivalent circuits of the impedance of a planar conductometric transducer  with an interdigital comb topology, consisting of  interelectrode and Faraday impedances is proposed.  The frequency characteristics of the impedance parameters of the transducer samples and the  electrical equivalent with averaged values of the parameters have been studied. A technique for determining the parameters of a three-element equivalent circuit, including solution resistance,  double layer capacitance, and charge transfer  resistance, has been developed and tested on a  series of transducer samples. The optimal operating  frequencies of the impedance-measuring channel are determined, and its schemes are developed. A  technique for estimating the parameters of the Warburg impedance of transducer samples is  demonstrated. The results obtained in the work  make it possible to determine the optimal operating  frequency range of biosensor systems and reduce  errors from the influence of the Faraday impedance. The possibility of extending the functions of such transducers by using the near-electrode layer  impedance parameters as informative ones is shown.