Portable measurement system for biological element

• Main Author: Teoh, Wong Wei
• Other Authors: Du Hejun
• Format: Final Year Project
• Language: English
• Published: 2015
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/62718
• Institution: Nanyang Technological University

Electrochemical Impedance Spectroscopy may be powerful to analyse impedance of various specimens, but existing commercial impedance machines are big and bulky. Furthermore, little work have done to develop it into compact and portable device for biological element testing. Therefore, this report presents a design for compact and portable EIS system for biological element. Before the designed circuit which uses Wien oscillator is being used to examine biological element, verification and validation was done using various methods and machines. Thereafter, electrochemical properties of potatoes and apples were studied using designed circuit. In the first experimental, investigation was done to study the effects of time on potato. Results shows negligible change in impedance for fresh potatoes varying with days. Another experiment was conducted to observe apple decay, focusing on the changes of parameters of equivalent circuit model. Results shows the conductance and capacitance decreased as signs of indication of localised fluid loss and destruction of cell structure caused by microbes. The approach shows promising results of using modified Wien oscillator as an alternative to determine physical properties of biological system using electrical impedance.