Construction of Amperometric Glucose Sensor using Carbon Nanotubes and IO4-oxidized GOx

Abstract

Multi-wall carbon nanotubes (MWNTs) functionalized with amino groups were prepared via silane treatment. The resulting amino terminated MWNTs (AMWNTs) exhibited an improvement of dispersion in water, which was clearly indicated by changes visible to the naked eye. Here, AMWNTs were applied to construct glucose biosensors with IO4-oxidized glucose oxidase (IO4-oxidized GOx) through the layer-bylayer (LBL) covalent self-assembly method without any cross-linker. The marked decrease in the overvoltage for the reduction of dissolved oxygen facilitated convenient low-potential stable detection of the glucose. The enzyme electrode exhibited good electrocatalytic response toward the glucose and that the response increased with the number of GOx/AMWNTs bilayers, suggesting that the analytical performance such as sensitivity and detection limit of the glucose biosensors could be tuned to the desired level by adjusting the number of deposited GOx/AMWNTs bilayers.