Enzymatic sensing of glucose in artificial saliva using a flat electrode consisting of a nanocomposite prepared from reduced graphene oxide, chitosan, nafion and glucose oxidase

• DOI: 10.1007/s00604-016-1753-3
• Publication Date: 2016-01-27T10:49:46Z
• Authors: Amal Rabti; Wicem Argoubi; Noureddine Raouafi
• Keywords: 02 engineering and technology; 0210 nano-technology

We report on the preparation of a nanoporous flat electrode by drop casting a nanocomposite consisting of reduced graphene oxide (rGO) and chitosan onto a polyester substrate. An underlying conductive surface is not required. The nanocomposite was characterized by scanning electron microscopy and electrochemical impedance spectroscopy. The 3D network of the composite was used as a scaffold for the immobilization of glucose oxidase (GOx). A well-defined signal related to direct GOx electrochemistry was registered and used to monitor levels of glucose. The resulting biosensor displays a linear response to glucose with a detection limit of 5 μM (at an S/N ratio of 3) and a sensitivity of 41.7 μA⋅mM−1∙cm−2. The sensor was applied to the determination of glucose in artificial saliva.