Self-activated microbatteries to promote cell death through local electrical stimulation

Abstract

Abstract Electrical stimulation of cells offers a viable alternative route to treat diseases like cancer that account for several deaths despite sophisticated treatments. While micro/nanoscale systems have demonstrated to regulate cell activity by inducing electrical signals, many of these rely on external excitation sources for operation. In this work, we present an array of Al-H2O based microbatteries of dimensions smaller than a single cell to induce localized electrical impulses by involving no excitation sources outside the cellular environment, i.e., self-stimulation, for a limited operation time. The fabricated structure allows microbattery activation, i.e., produces a voltage or current flow, on contact with the ionic species in biological medium. The study explores the response of human osteosarcoma cells (Saos-2) under the influence of these generated electrical impulses. The microbatteries allowed proliferation of Saos-2 cells when configured to operate in an open-circuit fashion, while they induced cell death in a short-circuited operation due to a current flow causing a drastic reduction in cell viability to 13.5%. The self-stimulated current produced a profound cytotoxic effect up to 24 h of incubation before the microbatteries became inactive. An up-scaled model and fabricated test-structure further explores the electrochemical characteristics of Al-H2O based batteries and their effect on relevant parameters like pH. The overall results suggest prospects for a non-invasive treatment in cancer therapy, neuromuscular system, neurological disorders, chronic treatments, tissue regeneration and other electrically active systems by the application of a self-stimulated electrical signal.