New method for the detection of enzyme immobilized on Si-based glucose Biosensors

Glucose oxidase molecular layers immobilized on planar and porous SiO
₂
substrates were characterized with techniques commonly used in microelectronics technology. Both planar and porous SiO
₂
were used as inorganic platforms for the enzyme bonding. The immobilization protocol on planar SiO
₂
was characterized using contact angle, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS), while energy dispersive X-ray analysis (EDX) coupled with scanning electron microscopy (SEM) were used on porous SiO
₂
samples. A conclusive confirmation of the enzyme presence in the SiO
₂
matrix was obtained by gold nano particles labeling. This last measurement technique could be implemented to determine the enzyme concentration in the porous SiO
₂
layer.