Fiber-based optrodes Light delivery for optogenetics

Abstract:
We present a novel approach for developing a miniaturized fiber-based tool, which is able to achieve precise light emission and to reliably deliver light to targeted area of brain tissue with the ability of simultaneous electrophysiological recording. In order to achieve light delivery and electrophysiological recording, we present an optrode: a combined optical and electrical probe containing three separate metal electrodes deposited on the cylindrical surface of an optical fiber. Since the insertion leads to local tissue trauma and seriously affects the performance of the optrode, we present a fiber tip tapering procedure as a way of minimizing the tissue damage induced by penetration. Here we present our technique, which provides the possibility of achieving tapered fiber tips with good optical quality and various cone geometries. Furthermore, we demonstrate electrode fabrication on the curved surface of the optical fiber.