(29k) Elucidating the Electric Field Distribution in a Two Planar Electrode Assembly with a Nanoporous Polycarbonate Membrane and Cell Monolayer Hybrid

Nanopore electroporation (NanoEP) is a gentle and highly efficient transfection method that utilizes an insulating nanoporous polycarbonate track-etched (PCTE) membrane to localize the electric field along the cell membrane over the nanopores (Figure 1). The efficiency of this system is highly dependent on the electric field; however, certain factors that alter the electric field distribution can affect the overall uniformity of delivery and removal in NanoEP. There is a lack of information on the distribution of this electric field in two planar electrode assemblies of NanoEP in real time, often due to the lack of optically clear materials. Indium tin oxide (ITO) is an optically clear electrode that can allow for real time visualization of cargo removal in a cell monolayer on a PCTE membrane. In this study, we investigate the electric field distribution using an optically clear nanoporous PCTE membrane and cell monolayer hybrid in a two planar ITO electrode polydimethylsiloxane (PDMS) device assembly. Our results show that this hybrid material allows for mapping of the electric field when depleting a fluorescently labeled small molecular cargo, calcein. In a circular well, radial depletion is observed from the outside perimeter of the well to the center of the well. As shown in Figure 2, there is a higher rate constant at the perimeter of the device (Radial Bin No 6) than compared to the center (Radial Bin No 1). We observed similar trends with different device geometries and electrical parameters, where a higher depletion rate occurred at the edge of the device compared to the center. Using real time visualization of a fluorescently labeled molecule on a PCTE membrane and cell monolayer hybrid material will provide insight on the electric field distribution in NanoEP. Optimal device geometries and electrical parameters will provide an even distribution of the electric field, and in turn, a uniform platform for delivery and depletion of cargo in NanoEP.