Electrochemical sensing platform based on the quaternized cellulose nanoparticles/acetylene black/enzymes composite film

Quaternized cellulose nanoparticles (QCs)/acetylene black (AB)/enzymes composite electrodes, constructed by simple physical inclusion of the enzyme into the bulk of the electrode matrix, have been used for the amperometric detection of hydrogen peroxide (H2O2) and glucose. The new composite material combines the unique and attractive electrocatalytic behaviors of QCs and acetylene black, with excellent biocompatible, electric conductivity and large specific surface area. The modified electrodes were electrochemically characterized, and bioelectrocatalytic reactions were followed. The resulting composite film promotes the direct electron transfer of GOD and Hb immobilized in the films effectively with fast electron transfer rates. The prepared enzyme/QCs-AB composite film exhibited high electrocatalytic performance to hydrogen peroxide (H2O2) and glucose, with fast response, wide linear range, good sensitivity and excellent stability. The successful practice of using the QCs-AB modified electrode for the direct electrochemistry and bioelectrocatalytic activity of enzymes offers an efficient strategy and a new promising platform for the construction of unmediated enzyme biosensors. (C) 2012 Elsevier B.V. All rights reserved.