Physico-chemical studies of indium tin oxide-coated fiber optic biosensors

Our recent studies have shown that thin films of indium tin oxide (ITO) could be deposited onto non-conductive optical fiber tips, which were then used as working electrodes for the electrochemical deposition of polymers with reactive groups (biotin), so as to create a biosensor. Physico-chemical properties of ITO thin films (260 nm) deposited by radio frequency (r.f.) sputtering onto fiber optics have been studied and compared to the existing literature on a flat glass surface. The film properties vary particularly for different oxygen pressures used during deposition. The microstructure of these thin films is determined using X-ray diffraction, transmission electron microscopy, scanning electron microscopy and atomic force microscopy.