Application of electrochemical impedance spectroscopy in sensor systems, devices, and related methods

摘要

A diagnostic Electrochemical Impedance Spectroscopy (EIS) procedure is applied to measure values of impedance-related parameters for one or more sensing electrodes. The parameters may include real impedance, imaginary impedance, impedance magnitude, and/or phase angle. The measured values of the impedance-related parameters are then used in performing sensor diagnostics, calculating a highly-reliable fused sensor glucose value based on signals from a plurality of redundant sensing electrodes, calibrating sensors, detecting interferents within close proximity of one or more sensing electrodes, and testing surface area characteristics of electroplated electrodes. Advantageously, impedance-related parameters can be defined that are substantially glucose-independent over specific ranges of frequencies. An Application Specific Integrated Circuit (ASIC) enables implementation of the EIS-based diagnostics, fusion algorithms, and other processes based on measurement of EIS-based parameters.

主权项

1. A method of calibrating a sensor, comprising:
performing an electrochemical impedance spectroscopy (EIS) procedure for a working electrode of a sensor to obtain values of at least one impedance-based parameter for said working electrode; performing a bound check on said values of the at least one impedance-based parameter to determine whether said at least one impedance-based parameter is in-bounds and, based on said bound check, calculating a reliability-index value for said working electrode; and determining, based on the value of said reliability index, whether calibration should be performed, or whether calibration should be delayed until a later time.