A Biomimetic Device to Restore Lost Vision to the Blind

In nature, nanopores play an essential role in a number of biological functions. The malfunctioning of these biological channels can therefore have devastating effects on the well being of their host. Synthetic nanopores have emerged as a powerful tool to better understand biological nanopores and could potentially restore lost functionality to such systems. The key to unlocking this immense potential of synthetic nanopores is the ability to functionalize the nanopore with any desired molecule, such as ligands, proteins, crown ethers, etc. By developing a methodology to attach any molecule of choice, we will be able to quickly explore potential candidates to achieve similar functionality as biological channels. One particular biological system of interest is the retinal system, gaining popularity with the recent success of cochlear implants. Several recent attempts have restored partial functionality to vision, but have limitations due to power constraints and non-renewable sources of stimulation. It was recently established that a small increase in the extracellular potassium ion concentration can effectively stimulate neural tissue. Dr. Theogarajan has proposed a novel synthetic ion pump that will function by sequestering local potassium ions from extracellular fluid, ultimately leading to a renewable and low power device. We report here on potential candidates for a potassium selective channel, with measurements on single nanopores in Silicon Nitride and Aluminum Oxide and nanopores arrays in Polycarbonate.