Preparation and biosensing performance of porous-alumina-assisted gold nanostructures on substrates

Abstract

Gold based nanosize structures such as nanoparticles and nanowires are considered as important building blocks for nanotechnology to be used for construction of sensing micro- and nanodevices because of their excellent optical, electrical and mechanical properties. Here we synthesize via porous-alumina-assisted anodizing and electrodeposition perfect arrays of gold nanodots and nanorods, upright standing, spatially separated and highly aligned on a conductive substrate, which are expected to have exceptional performance in nanoscale electronic, optoelectronics and sensing applications. Biosensing potential of the nanostructured electrodes was assessed by examining electrochemical properties of a protein layer grafted on the electrode for Creactive protein (CRP) detection using CRP-antibody immobilization method with protein G intermediate layer. The laboratory prototype of immunosensor revealed reproducible, rapid and stable response with a low limit for CRP-antigen detection of 100 fg·ml-1