Wireless Force-Inducing Neuronal Stimulation Mediated by High Magnetic Moment Microdiscs.

Non-invasive manipulation of cell signaling is critical in basic neuroscience research and in developing therapies for neurological disorders and psychiatric conditions. Here; we describe the wireless force-induced stimulation of primary neuronal circuits through mechanotransduction mediated by magnetic microdiscs (MMDs) under applied low-intensity and low-frequency alternating magnetic fields (AMFs). MMDs were fabricated by top-down lithography techniques that allow for cost-effective mass production of biocompatible MMDs with high saturation and zero magnetic magnetic moment at remanence. MMDs are utilized as transducers of AMFs into mechanical forces. When MMDs are exposed to primary rat neuronal circuits their magneto-mechanical actuation triggers the response of specific mechanosensitive ion channels expressed on the cell membranes activating ∼50% of hippocampal and ∼90% of cortical neurons subjected to the treatment. Mechanotransduction was confirmed by the inhibition of mechanosensitive transmembrane channels with Gd3+ . Mechanotransduction mediated by MMDs caused no cytotoxic effect to neuronal cultures. This technology fulfills the requirements of cell-type specificity and weak magnetic fields; two limiting factors in the development of non-invasive neuromodulation therapies and clinical equipment design. Moreover; high efficiency and long-lasting stimulations were successfully achieved. This research represents a fundamental step forward for magneto-mechanical control of neural activity using disc-shaped micromaterials with tailored magnetic properties. This article is protected by copyright. All rights reserved.