Abstract: Various examples are provided related to nanofiber networks that can mimic in vivo physiology. In one example, a scaffold includes a nanofiber membrane extending across a scaffold opening. The nanofiber membrane can include a stack of nanofiber layers that include nanofibers disposed with a controlled orientation or direction and a controlled spacing. The nanofibers are cross-linked with nanofibers of an adjacent nanofiber layer. The scaffold can be incorporated into a transwell insert or plate. In another example, a microfluidic chip can include a first channel layer with a first fluid channel; a second channel layer comprising a second fluid channel; and a scaffold including a nanofiber membrane disposed between the first and second channel layers. The first and second channels cross each other.

Abstract: In accordance with the purpose(s) of the present disclosure, as embodied and broadly described herein, the disclosure, in one aspect, relates to methods for modifying cells such as, for example, changing shape, cell force, and/or modifying structural integrity of the cells. In a further aspect, the disclosure relates to controlling membrane permeability in cells by applying an electric current, where the cells are in contact with a polymeric nanofiber array and wherein direction and voltage of the electric current can be modified to induce the desired cellular response. In some aspects, the method results in higher survivability for cells during electroporation, greater permeability to molecules and/or drugs of different sizes, and greater transfection efficiencies for rare primary cells.