Available at: https://digitalcommons.calpoly.edu/theses/2832
Date of Award
6-2024
Degree Name
MS in Electrical Engineering
Department/Program
Electrical Engineering
College
College of Engineering
Advisor
Benjamin Hawkins
Advisor Department
Electrical Engineering
Advisor College
College of Engineering
Abstract
ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY (EIS) provides a method for collecting the electrical frequency dependent characteristics of biological materials. The Biomedical Microsystems Lab has developed a 16-channel cell culture with inte- grated electrode arrays for characterizing the electrical impedance of cells. Previous work has condensed the EIS technology to accompany the multichannel cell culture onto a Printed Circuit Board Assembly (PCBA) to replace a high-cost physical relay multiplexer (MUX) and impedance analyzer system with a low-cost solid-state analog MUX and Analog Discovery 2 (AD2). In this paper, the current PCBA and MUX are compared to system improvements, decreasing measurement error by 0.3-0.5% around 100Hz and 25-28% around 1MHz. The main change replaces the 16-channel MUX with four 4-channel MUX’s. The integrated circuit (IC) replacement decreases exces- sive gain contributed by the PCBA, extends the bandwidth of the original system, and flattens the frequency response around 1MHz. Each board revision is compared to justify variations made to the system accuracy. The resulting measurement data and EIS PCB gain characteristics can be applied in the future to improve cell growth quantification.