Application of electrochemical impedance spectroscopy in sensor systems, devices, and related methods
First Claim
1. A method of calculating a single, fused sensor glucose value based on respective glucose measurement signals of a plurality of redundant sensing electrodes, comprising:
- performing respective electrochemical impedance spectroscopy (EIS) procedures for each of the plurality of redundant sensing electrodes to obtain values of at least one impedance-based parameter for each said sensing electrode;
measuring the electrode current (Isig) for each of the plurality of redundant sensing electrodes;
calculating a bound-check reliability index and a noise-check reliability index for each said sensing electrode based on said measured Isig and said values of the at least one impedance-based parameter;
calculating a dip reliability index for each said sensing electrode based on one or more of said at least one impedance-based parameter;
calculating a sensitivity-loss reliability index for each said sensing elect le based on one or more of said at least one impedance-based parameter;
calculating a single fused Isig based on the respective bound-check reliability index, noise-check reliability index, dip reliability index, sensitivity-loss reliability index, and respective Isig of each of the plurality of redundant sensing electrodes; and
calibrating said single fused Isig to obtain said single fused sensor glucose value, wherein said single fused Isig is calibrated by using a blood glucose (BG) value.
1 Assignment
0 Petitions
Accused Products
Abstract
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.
-
Citations
21 Claims
-
1. A method of calculating a single, fused sensor glucose value based on respective glucose measurement signals of a plurality of redundant sensing electrodes, comprising:
-
performing respective electrochemical impedance spectroscopy (EIS) procedures for each of the plurality of redundant sensing electrodes to obtain values of at least one impedance-based parameter for each said sensing electrode; measuring the electrode current (Isig) for each of the plurality of redundant sensing electrodes; calculating a bound-check reliability index and a noise-check reliability index for each said sensing electrode based on said measured Isig and said values of the at least one impedance-based parameter; calculating a dip reliability index for each said sensing electrode based on one or more of said at least one impedance-based parameter; calculating a sensitivity-loss reliability index for each said sensing elect le based on one or more of said at least one impedance-based parameter; calculating a single fused Isig based on the respective bound-check reliability index, noise-check reliability index, dip reliability index, sensitivity-loss reliability index, and respective Isig of each of the plurality of redundant sensing electrodes; and calibrating said single fused Isig to obtain said single fused sensor glucose value, wherein said single fused Isig is calibrated by using a blood glucose (BG) value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21)
-
Specification