A process for forming a functionalized sensor for sensing a molecule of interest includes providing at least one single or multi-wall carbon nanotube having a first and a second electrode in contact therewith on a substrate; providing a third electrode including a decorating material on the substrate a predetermined distance from the at least one single or multi-wall carbon nanotube having a first and a second electrode in contact therewith, wherein the decorating material has a bonding affinity for a bioreceptors that react with the molecule of interest; and applying a voltage to the third electrode, causing the decorating material to form nanoparticles of the decorating material on the at least one single or multi-wall carbon nanotube.