Thermoplasmonic Optical Fiber for Localized Neural Stimulation.

Abstract

Thermoplasmonic effect-based neural stimulation has been suggested as an alternative optical neural stimulation technology without genetic modification. Integration of near-infrared light with plasmonic gold nanoparticles has been demonstrated as a neuromodulation tool on <i>in vitro</i> neuronal network models. In order to further test the validity of the thermoplasmonic neural stimulation across multiple biological models (<i>in vitro</i>, <i>ex vivo</i>, and <i>in vivo</i>) avoiding genetic modification in optical neuromodulation, versatile engineering approaches to apply the thermoplasmonic effect would be required. In this work, we developed a gold nanorod attached optical fiber technology for the localized neural stimulation based on a thermoplasmonic effect. A simple fabrication process was developed for efficient nanoparticle coating on commercial optical fibers. The thermoplasmonic optical fiber proved that it can locally modulate the neural activity <i>in vitro</i>. Lastly, we simulated the spatiotemporal temperature change by the thermoplasmonic optical fiber and analyzed its applicability to <i>in vivo</i> animal models.