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While classical electrochemical impedance spectroscopy (EIS) focuses on measurements from a single working electrode, dense active microelectrode arrays offer opportunities for new modes of sensing. Here we present experimental results with an integrated sensor array for electrochemical imaging. The system uses a 100 x 100 custom CMOS electrode array with 10 micron pixels, which measures impedance at frequencies up to 100 MHz. The sensor chip is uniquely designed to take advantage of the electrostatic coupling between groups of nearby pixels to re-shape the local electric field. Multiple bias voltages and clock phases create new types of signal diversity that will enable enhanced sensing modes for computational imaging and impedance tomography.
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Super-Resolution Electrochemical Impedance Imaging with a 100 x 100 CMOS Sensor Array
This paper presents a 100 x 100 super-resolution integrated sensor array for microscale electrochemical impedance spectroscopy (EIS) imaging. The system is implemented in 180 nm CMOS with 10 x 10 micron pixels. Rather than treating each electrode independently, the sensor is designed to measure the mutual capacitance between programmable sets of pixels. Multiple spatially-resolved measurements can then be computationally combined to produce super-resolution impedance images. Experimental measurements of sub-cellular permittivity distributions within single algae cells demonstrate the potential of this new approach.
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- Award ID(s):
- 2027108
- PAR ID:
- 10322164
- Date Published:
- Journal Name:
- 2021 IEEE Biomedical Circuits and Systems Conference (BioCAS)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/BioCAS49922.2021.9644965
