|
Optogenetics is known as a technique that genetically targets specific neurons to express light sensitive channel proteins and provides the capability to stimulate the central nervous system with millisecond precision: Compared to deep brain stimulation, which affects bigger regions of the brain and thereby making it impossible to precisely stimulate individual cells, optogenetics offers the possibility of targeted neuron stimulation without affecting surrounding neurons. Numerous optogenetic devices have been developed for light delivery and simultaneous electrophysiological recordings. Most of them consist of an optical fiber and separate micro electrodes attached to the optical fiber. Even such small electrodes can induce tissue damage. In order to reduce the tissue damage, we present a fiber-based optogenetic light-delivery device with microelectrodes coated on the surface of the optical fiber. Our work uses metalized optical fiber, in order to deliver the light and simultaneously record the induced modulation (electrophysiological signals) with minimum tissue damage. Light delivery is done from the optical fiber tip, while microelectrodes are fabricated from the metal thin-film. These coating serves as the microelectrodes are used for the recording of electrophysiological signals. In this work, we present the details of electrode micro-structuring on the optical fiber using sputtering process. We also present and comment on the results of resistance measurements of the sputtered electrodes. Currently, we use copper for electrode fabrication, later we foresee to utilize gold as a biocompatible electrode material.
|
