A high-resolution amperometric acetylcholine biosensor based on nano self-assembly of carbon nanotubes

We present a carbon nanotube thin film based device as a high-resolution acetylcholine sensor. Carbon nanotube and acetylcholinesterase thin films are self-assembled on a silicon substrate as conducting and sensing layers, respectively. Both films are deposited using layer-by-layer self-assembly process. The conductance of the carbon nanotube film is changed due to the generated hydrogen ions in the acetylcholine solution. The resolution of the device is measured as 100 pM. Due to its high resolution, small size, and low cost, the carbon nanotube biosensor has tremendous potential for applications to medical research and clinical diagnosis.