A novel ormosil based electrocatalytic biosensor for glucose/ethanol based on dehydrogenase modified electrode

Abstract

A novel ormosil material for designing electrocatalytic biosensors for glucose and ethanol based on dehydrogenase catalyzed reactions is reported. The electrode material is prepared using palladium-linked glycidoxypropyltrimethoxysilane, ferrocene monocarboxylic acid, trimethoxysilane and HCl. The ormosil prepared from these ingredients shows reversible electrochemistry of ormosil encapsulated ferrocene. The electrocatalytic oxidation of NADPH/NADH and subsequently novel dehydrogenase based biosensors for glucose and ethanol are developed. The results based on cyclic voltammetry and amperometry are reported. The enzyme sensors are developed based on the modification of electrode material by dehydrogenase enzymes. The modification of electrode material is made by two approaches of enzyme immobilization: immobilization of dehydrogenase within polyvinyl alcohol and sandwiching the dehydrogenase within two layers of ormosils among which the first layer being the electrode material itself and the second layer of ormosil prepared without palladium linkage precursor and ferrocene. The biosensor made by the second approach shows high stability and much better reproducibility of enzyme electrode performance. The results on glucose and alcohol sensing based on electrochemical measurements are reported.