Current implant technology exploits electrical signaling at the electrode-neural interface.  This approach has fundamental problems which limit both the performance and safety of the implants, bearing high  invasiveness. Inducing light sensitivity in living organisms is an alternative approach that provides ground breaking opportunities in neuroscience. Optogenetics is a spectacular demonstration of this, yet limited by the viral transfection of exogenous genetic material. The thesis regards alternative approaches aimed at NON-genetically inducing light sensitivity in cells or organism by using light-responsive nanostructures (0.1-1 μm) or molecular actuators  that trigger signaling cascades. The activity comprise the study of the photophysics of the actuators both in vitro as well in vivo, and their effects on investigated cells. Applications in medicine, neuroscience and bio engineering spans form artificial retina prosthesis for rescue vision in blind eyes to neuronal networks investigations, including brain, to muscle cells control.