Development of a continuous-flow, automated microfluidic device for single cell level electroporation

Electroporation is a powerful transfection technique that creates transient openings in the cell membrane by applying an electric field, allowing for the intracellular delivery of diagnostic and therapeutic substances. The ability to detect and control the degree of cell membrane permeability plays a key role in determining the size of the delivery payload, while safeguarding the overall cell viability. In order to create a universal electroporation system, this dissertation describes the development of a continuous flow electroporation microdevice that automatically detects, electroporates, and monitors individual cells for changes in permeability and delivery. In contrast to devices that immobilize individual cells for impedance analysis, this work demonstrates the capability to manipulate single cells under flow and real-time analysis of membrane permeabilization before and after electroporation, which dramatically increasing the number of cells which can be electroporated and analyzed. Using an electric circuit model, and Multiphysics computational tools, the key parameters for successful cell membrane permeabilization detection in a flow environment were determined. By varying the electric field parameters, we demonstrate the direct control of cell membrane permeabilization by electrically measuring the electroporation-induced cell membrane impedance change and by optically measuring the delivery of a fluorescent probe. Viability of the electroporated cells following collection also demonstrates a correlation with the applied pulse strength. By extending the device capability to include dynamic pulse adjustment according to the real-time feedback information on cell viability, an intelligent electroporation system capable of potentially maximizing delivery efficiency and cell viability can be thus realized.Ph.D.Includes bibliographical referencesby Mingde Zhen