Electropolymerized architecture entrapping a trilacunary keggin-type polyoxometalate for assembling a glucose biosensor

A new design to obtain an amperometric glucose biosensor based on glucose oxidase (GOx) immobilization on an electropolymd. matrix [poly (1,8 DAN)] entrapping a trilacunary Keggin type polyoxometalate (Fe4POM) deposited on a graphite electrode was proposed. Some exptl. evidences suggest that the modified conducting polymeric matrix consists in a multilayer architecture, formed from pos. charged conductive poly (1,8 DAN) alternating with the neg. charged (Fe4POM). At an applied potential of -0.04 V (vs. Ag/AgCl, KClsal), the batch amperometric response to glucose of the G/Fe4POM-poly(1,8 DAN)/GOx modified electrode is characterized by a sensitivity of 19.8±2.4 mA M-1 cm-2, a linear range between 2.5 to 20 mM glucose, a response time less than 40 s and a detection limit of 1.2 mM glucose (for S/N = 3).