Imaging Supported Lipid Bilayers during Electroporation Process using Atomic Force Microscopy

Complementary to conventional vaccination, biological therapeutics such as those based upon nucleic acids, offer advantages in terms of safety, efficacy, and production. Their efficacy critically depends on how they are delivered and their interactions with cell membrane. Electroporation is a powerful way to deliver biological therapeutics, that is compatible with most cell types and cargoes and therefore a flexible and powerful alternative to other intracellular delivery methods. It enables the delivery of exogeneous species into cells by creating transient and reversible nanopores in the cell membrane upon an applied electric pulse. However, the lack of fundamental understanding in the dynamic behaviors and hydration properties of cell membrane, with lipid bilayers as the backbone, hinders the design of efficient non-viral transfection protocols and biomimetic systems such as liposomes and vesicles for biotechnological and medical purposes. Supported lipid bilayers (SLBs), a structure that mimics the cell membrane, simplify the complexity of cellular membrane structures while providing stability for in vitro studies. Here we use the electrochemistry-3D-atomic force microscopy as a promising tool to offer direct imaging and obtaining multiparametric information including both topographic, hydration, and mechanical information of the SLBs as they respond to an external electric field. This work provides fundamental understanding of the electroporation process and will be critical in achieving efficient delivery without causing irreversible membrane damage.