| Nano TiO2 (Titania) was synthesized by using TiCl4 and Ti(OBu)4 and the crystal phase transferred after it was calcined at different temperature. The analytical methods such as UV-Vis spectrometry, Laser Particle Size Analysis (LPSA), X-ray diffraction analysis (XRD) and Scanning Electron Microscopy (SEM) were applied to characterize the properties of nano-TiO2. The nano particles which synthesized by TiCl4 has small size, good water-solubility and good adsorption to ITO glass. The TiO2 modified ITO (Indium-Tin oxide) glass electrode (TiO2/ITO electrode) was prepared and its sensitization for electrochemiluminescence (ECL) of luminol was studied. TiO2/ITO electrode which was calcintrated at the temperature of 650°C that contained 43.46% anatase shows highest sensitization. The ECL intensity of luminol was enhanced 7.5 times on this electrode compared with the bare ITO glass electrode. The aggregation has been avoided effectively because TiO2 was modified previously and than send to be calcined, so the mixed crystal was obtained while the size of the particles was controlled. A group of seven mixed crystal TiO2/ITO electrodes were used to the detection of ECL and the RSD was 1.88%. One electrode has been used for the detection of ECL for 7 days and the damping is 5.88%. The result shows that this kind of electrode has good stability and reproducibility.Based on TiO2/ITO electrode, GOD was modified by Chitosan, sol-gel and Nafion to make GOD/TiO2/ITO electrode for glucose detection. Among these methods, using Nafion can get the best result. Besides, the modification time, the buffer system, the pH of the buffer system and the temperature were taken into consideration. Because of the high specific surface area and good biological compatibility of TiO2, more enzyme was loaded, so the sensibility of GOD/TiO2/ITO was higher than GOD/ITO. The liner range was 4×10-51.8×10-2 mol/L and the detection limit was 2×10-5 mol/L.
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