Design and implementation of portable potentiostat

Sensors are used to examine a biological or chemical substance or event and detect changes. A biosensor converts the amount or type of analyte to an electric signal in its environment. The biological material in the environment can be examined quantitatively and qualitatively from the measured signal. Biosensors are classified into three different classes according to their transducer structure: optical, weight-based, and electrochemical. An electrochemical sensor structure consists of an electrochemical cell and a potentiostat. A portable, wireless, and low-cost potentiostat capable of performing voltammetric and amperometric measurements has been designed and implemented in electrochemical measurements in this thesis. ESP32 has been used as a microcontroller in this potentiostat. The voltage that other hardware elements need to work has been supplied via the microcontroller, thus providing portability. Additionally, the Bluetooth protocol has provided wireless communication between the microcontroller and the user. Then, this realized potentiostat has been calibrated with a dummy-cell circuit. The calibrated potentiostat is used for glucose and ascorbic acid measurement experiments to test the amperometric and voltammetric measurement functionality, respectively. As a result of these experiments, the regression rates in glucose and ascorbic acid quantitative experiments were 88% and 89%, respectively. Keywords: Potentiostat, ESP32, electrochemical sensors, portable