Enzyme-based electrochemical biosensors are analytical devices with great potential in various fields, thanks to their specificity, high sensitivity, and the possibility of automation and miniaturization. The analytical performance of these electrochemical devices can be remarkably improved by the employing of advanced nanomaterials due to the important features of these materials, including great effectiveness in electron transfer related to its high surface area and conductivity. This chapter reports the recent applications of different enzymatic biosensors based on the modification of the working electrode with nanomaterials, including fullerenes, graphene, carbon nanotubes (CNTs), carbon and graphene quantum dots (QDs), metallic nanoparticles (NPs), and inorganic QDs. The reported devices are categorized according to the target biomolecule, and their description has considered not only the nanomaterial used but also the type of electronic transfer that takes place (direct or mediated) as well as the enzymatic mechanism involved.
