Impedance Spectroscopy of Single Cells Using Embedded AgPDMS Electrodes

This thesis presents a microfluidic device with wide channels and embedded AgPDMS electrodes for measuring the electrical properties of single cells. The work demonstrates the feasibility of using a large channel design and embedded electrodes for impedance spectroscopy to circumvent issues such as channel clogging and limited device re-usability. AgPDMS electrodes were formed on channel sidewalls for impedance detection and cell characterization. Equivalent circuit models were used to interpret multi-frequency impedance data to quantify the cytoplasm conductivity and specific membrane capacitance of each cell. T24 cells were tested to validate the microfluidic system and modeling results. Comparisons were then made by measuring two leukemia cell lines (AML-2 and HL-60) which were found to have different cytoplasm conductivity values (0.29 +/- 0.15 S/m vs. 0.47 +/- 0.20 S/m) and specific membrane capacitance values (41 +/- 25 mF/m2 vs. 55 +/- 26 mF/m 2).