Nanotechnology provides us with tools to create functional materials, devices, and systems by controlling materials at the atomic and molecular scales, and at the same time make use of novel properties and phenomena. Considering that most chemical and biological sensors, as well as many physical sensors, depend on interactions occurring within the nano scale range, the impact that nanotechnology will have on the sensor world is significant. Nanotechnology enabled sensors find applications in several novel fields such as sensing single molecules, bio-hazards, toxic chemicals, gas sensors, process control and diagnostics. Application of nanostructured materials for biological applications, biologically assisted nanofabrication, and the development of next-generation of biosensors and biomedical instrumentation for improved sensing is increasingly attracting interests in the scientific community. .