화학공학소재연구정보센터
Journal of Electroanalytical Chemistry, Vol.419, No.1, 93-98, 1996
Studies on Employing Tetrathiafulvalene as an Electron Shuttle Incorporated in a Montmorillonite-Modified Immobilization Matrix for an Enzyme Electrode
A new strategy to immobilize an electron transfer mediator for construction of a second generation amperometric biosensor is described. The strategy was implemented with the mediator-oxidase reactor system. Non-soluble tetrathiafulvalene (TTF) as a mediator and glucose oxidase (GOD) were co-immobilized in the montmorillonite-modified bovine serum albumin (BSA) + glutaraldehyde matrix on a glassy carbon electrode surface. The mediating redox couple, the non-soluble TTF and the soluble TTF+ ions were immobilized by sodium montmorillonite colloidal particles via cation exchange and adsorption, whereas GOD was immobilized with a cross-linker, the BSA + glutaraldehyde. Cyclic voltammetry and potentiostatic measurements demonstrated that TTF incorporated in the immobilization matrix could shuttle electrons efficiently between GOD and the electrode. The linear response range of the sensor was from 1.0 x 10(-4) to 8.0 x 10(-3) M and its response time to glucose was less than 10 s.