Investigation of the binding kinetics and electrochemical properties of in situ reconstructed apo-GOx using electrodes with electrodeposited FAD cofactor

Abstract

Herein, the electroanalytical properties of in situ reconstructed apo-glucose oxidase (apo-GOx) on electrodes modified with electrodeposited cofactor flavin adenine dinucleotide (FAD) were studied in the absence of any diffusional electron mediators. In the electrodeposited sensing layer, the order of enzyme assembly using the same building blocks (e.g., spatially separated apo-GOx with FAD cofactor or native holo-GOx with entrapped cofactor) significantly affected the electrodes’ electroanalytical performance. These electrodes exhibited a pronounced real time current difference (i), and the work of in situ reconstructed apo-GOx, compared with a native electrodeposited holo-GOx analogue, was not limited by oxygen depletion (ii). This knowledge was subsequently used to profile several types of apo-GOx.