Nanomaterials are acquiring a big impact on development of electrochemical biosensors. Nanotechnology brings new possibilities for biosensors construction and for developing novel electrochemical bioassays. Moreover, the high sensitivity of electrochemical transducers, coupled to their compatibility with modern micro-fabrication technologies, independence of sample turbidity or optical pathway, low cost (disposability), portability, and minimal power requirements, make them excellent candidates as a transducer system.