Nanoscaled redox active protein adsorption on Au-dot arrays: An electrochemical scanning probe microscopic investigation for application in nano-biodevices

Highly dense and uniform protein dot arrays on Au-nanodots using size controllable method were fabricated on indium tin oxide (ITO) substrate in order to develop an electrochemical nanobiochip. Cysteine modified azurin was directly immobilized on the fabricated Au-nanodots without any linker materials. Atomic force microscopy was used for characterizing Au-dots formed on ITO substrate. Electrochemical scanning tunneling microscopy (ECSTM) revealed the monolayer formation with an in situ cyclic voltammetry to observe redox behaviour of both bare Au-dots and protein immobilized Au-dots. I–V characteristics were obtained on both bare Au-dots and protein immobilized Au-dots structured on ITO conductive electrodes.