Round Well Inset for Uniform Electric Field Distribution in Electroporation Applications

Uniform electric field distribution in electroporation is crucial for achieving the effective localized delivery of drug molecules. Currently, in vitro electroporation studies on adherent cells lack a standardized test setup for obtaining consistent and repeatable results, unlike in vitro electroporation studies on cell suspensions that use electroporation cuvettes, which provide uniform electric field distribution. Considering this, we designed, built, and tested a novel inset design for low-volume round well plates, such as the 24- and 96-well plates which are most commonly used in cell culture labs. The inset design was realized using 3D printing and experimentally tested using potato phantoms and HeLa cells. Finite element analysis (FEA) was used to compute the electric field distribution in the round well plates with and without the inset. The FEA indicated that the electric field contour map at the bottom of the well with the inset had a more uniform electric field distribution, with an average value close to the expected 1000 V/cm. In contrast, it was only 840 V/cm without the inset, indicating non-uniform electric field distribution. Uniform electric fields were also obtained using the inset for the potato phantoms and the HeLa cells, indicating the merit of the inset and its usability with low-volume cell culture well plates, which enable the transfer of cells for various assays without additional steps, as well as its cost-effectiveness.