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A potentiostat is an analytical device and a crucial component in electrochemical instruments used for studying chemical reaction mechanisms, with potential applications in early diagnosis of disease or critical health conditions. Conventional potentiostats are typically benchtop devices designed for laboratory use, whereas a wearable potentiostat can be interfaced with biochemical sensors for disease diagnostics at home. This work presents a low-power potentiostat designed to connect with a sensor array consisting of eight to ten working electrodes. The potentiostat is capable of running Electrochemical Impedance Spectroscopy and Cyclic Voltammetry. The system is powered by lithium-ion batteries and uses Bluetooth for data transmission to the user. A single ARM M4 microcontroller, integrated with a Bluetooth low-energy radio module, controls the entire system. The accuracy, reliability, and power efficiency of the potentiostat were evaluated and compared against existing commercial benchtop potentiostats. Additionally, we have outlined future steps to enhance circuit miniaturization and power efficiency, aiming to develop fully integrated wearable sensing devices comparable in size to a wristwatch.
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A High-Speed Charge Injection Circuit for Nanosecond-Scale Electrochemical Measurements
This paper describes a GaNFET-based high-speed charge injection circuit to study fast redox processes at electrode-electrolyte interfaces. The circuit allows the rates of electrode processes, which are much faster than those accessible with a conventional potentiostat, to be measured. It is able to inject charge across the interface within a few nanoseconds, and also to hold the potential generated across the cell following injection for up to 1 s without appreciable (less than 1%) decay. In addition, the circuit can still monitor the current flowing through the cell, as in a conventional potentiostat. Preliminary test results with both a dummy load and a custom two-electrode electrochemical cell confirm the functionality of the proposed circuit.
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- Award ID(s):
- 1808592
- PAR ID:
- 10269343
- Date Published:
- Journal Name:
- 2020 Moratuwa Engineering Research Conference (MERCon)
- Page Range / eLocation ID:
- 319 to 324
- 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/MERCon50084.2020.9185286
