Implantable Photoacoustic and Microwave Neural Interface

High precision neuromodulation is a powerful tool for fundamental studies in neuroscience and potential treatments for neurological disorders. Here we report new developments in implantable non-genetic photoacoustic and microwave neural interfaces for high precise neuromodulation in retina and brain. First, we will discuss our design of biocompatible soft photoacoustic retina protheses. We confirmed successful blind retina stimulation through a PDMS-based photoacoustic film safely with a spatial resolution of 50 microns ex vivo and in vivo. These results show the potential of using optoacoustic signal to drive activity in photoreceptor-damaged retinas. Second, we will report an implantable miniaturized multifunctional fiber integrating with electrodes for simultaneous stimulation and recording in brain in vivo. Successful electrophysiology recording upon photoacoustic stimulation has been demonstrated in mouse brain acutely as well as up to 1 mon after implantation of the stimulator. Such devices open up potential for improved closed-loop stimulation in deep brain stimulation without the interference between the conventional electrical stimulation and recording. Lastly, we will discuss a miniaturized millimeter size microwave antenna as a wireless implantable neural interface to inhibit neural activities in vitro, ex vivo and in vivo. Suppression of seizure activities in brain in an epileptic rodent model has been achieved using low intensity microwave together with the implanted microwave antenna 6-10 time less than the FDA microwave threshold.