Poly(ethylene oxide)-LiClO 4 -TiO 2 organicinorganic hybrids were synthesized for Li-polymer battery electrolytes using sol-gel processing. The hybrids containing TiO 2 component showed the uniform film formation and also increased ionic conductivity. The hybrid films containing 10 wt% TiO 2 showed the smooth surface morphologies and also the highest ionic conductivity. The molecular-level hybrid formation between PEO and TiO 2 components was identified using FTIR analyses. The hybrids containing TiO 2 -Al 2 O 3 mixtures showed the enhanced ionic conductivity compared to those containing only TiO 2 most probably due to the Lewis acidic group formation at the surface of Al 2 O 3 components. The PEO-LiClO 4 -TiO 2 -Al 2 O 3 hybrids showed high stability both in ionic conductivity and crystallinity. By the sol-gel processing two inorganic components were successfully introduced in the PEO matrix and high-performance solid electrolytes were achieved.

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Pyrrole-titania hybrid films were electropolymerized on platinum electrodes and used for the entrapment of glucose oxidase ͑GOD͒ through chronoamperometry. The electrodes deposited in a sodium dodecyl sulfate solution showed higher oxidation current values than those deposited in a phosphate buffer solution. A possible mechanism for this difference was proposed based on the increase in the amount of GOD attachment, originating from the slow diffusion rate of large dodecyl sulfate anions. Hybrid-GOD electrodes revealed enhanced sensitivity with the concentration variation of glucose solution compared to pyrrole-GOD electrodes.Recently, research on the development of high-performance glucose biosensors has been highlighted due to the rapid increase in diabetes incidences. 1-10 Electrochemical enzyme sensors based on glucose oxidase ͑GOD͒ embedded polymer matrix are the most popular form; however, these systems reveal critical problems for applications such as breakdown of structure and leakage of enzyme out of sensors due to swelling of the polymer component and shortage of thermal stability. Polymer-silica hybrid system has been introduced to resolve the problems of polymer-GOD systems due to ease of forming homogeneous organic-inorganic hybrids. 11,12 However, these polymer-silica-GOD hybrid systems also show some critical drawbacks such as low reliability due to fragility and low functionality of enzyme due to the acidic condition during electrode fabrication. 13,14 Polymer-titania-GOD hybrid system would be an alternative to overcome the problems of polymer-silica-GOD hybrid system because this system can prevent enzyme leakage out of the hybrid sensors and maintain enzyme functionality using near chemical neutrality conditions. Dong et al. 4 and Ju et al. 5 fabricated polymertitania-GOD hybrid sensors by simple dropping or evaporating; however, their methods cannot be applied to the achievement of microbiosensors that can give better benefits for glucose measurement such as increased sensitivity and reduced amount of blood needed for the tests.In this study, pyrrole-titania hybrids were developed as a host material for the immobilization of GOD and electropolymerization was employed for the construction of bioelectrochemical electrodes. To increase the accuracy and lifetime of the sensors strong immobilization of GOD is of high importance and as many GOD molecules must be strongly entrapped in a hybrid matrix as possible. The sensor properties of the hybrid electrodes were analyzed and compared with pyrrole-GOD sensors.Pyrrole was fully distilled at 60°C in vacuum before use, and pyrrole monomer and titanium ͑IV͒ isopropoxide were dissolved in acetonitrile containing 0.1 M LiClO 4 with the molar ratio of 3:7. Pyrrole-titania hybrid stock solution was attached to platinum electrodes with 3 mm diameter by cyclic voltammetry ͑CV͒ at Ϫ1300 to ϩ1000 mV under nitrogen atmosphere to protect oxidation of the solution. Glucose oxidase ͑GOD͒ of 50,000 units was dissolved in 0.1 M phosphate buffer solution ͑PBS͒ and 0.1 ...