Aims of this work were the optimization of a protocol for the immobilization of a biological molecule on an inorganic platform, the manufacture of the sensing element of a biosensor and its full characterization. We used the Glucose Oxidase (GOD) as biological molecule to immobilize and Si-based surfaces as inorganic platform. To define and optimize the best protocol, non biological techniques such as Atomic force Microscopy (AFM), X-ray Photoelectron Spectroscopy (XPS) and Energy Dispersive X-ray (EDX) coupled to Scanning electron Microscopy (SEM), were used. AFM and XPS measurements were employed to study the surface coverage by linker molecule. Finally, EDX measurement allowed us to provide a direct measurement of the enzyme presence into the sample cross section. Through these techniques, normally used in the microelectronic field, we demonstrated that the immobilization protocol …