Design of a Galvanostat for Electrochemical Biosensors

• Main Authors: WU, HONG-YAN, 吳宏諺
• Other Authors: Chun-Yueh Huang
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/tj8h9y

碩士 === 國立臺南大學 === 電機工程學系碩博士班 === 107 === In this thesis, a galvanostat designed for the signal processing of electrochemical biosensors is proposed to analyze the resistance of electrochemical biosensors. The resistance of a biosensor can be obtained by controlling the input current to detect the biosensor’s voltage. In the proposed galvanostat, an EFM32 microprocessor chip is used to as the main controller, and an analog multiplexer is used to choose the different resistance to generate different analysis current (the current range is from ±20mA to ±10nA). Based on the cyclic voltammetry and the constant current coulometry methods, in the proposed galvanostat, the user can set the range of analysis current, scan rate, and scan segment, through the interface on the LabVIEW of personal computer, and then display the experiment result of the galvanostat. In system verification, at first, we use the resistors to simulate the biosensors to verify system function, according to Ohm's law. Secondly, the commercial printing electrodes are used to be the biosensors for analyzing different concentrations of K3[Fe(CN)6]. In the K3[Fe(CN)6] measurement, there are two ways to analyze K3[Fe(CN)6]: one is to analyze three different concentrations of K3[Fe(CN)6] at the same scanning rate using different currents, and the other is to analyze the same concentration of K3[Fe(CN)6] at different current scan rates. According to the experimental results, the galvanostat system architecture is proved to be correct. Keywords：Galvanostat, Electrochemical Biosensors constant current coulometry, User Interface, Embedded Systems