Reduced graphene oxide-nickel nanoparticles/biopolymer composite films for the sub-millimolar detection of glucose
Rahul Krishna1, José M Campiña2, Paula M V Fernandes2
1Centre for Research in Chemistry of The University of Porto (CIQUP), Department of Chemistry and Biochemistry, Faculty of Sciences, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal. jpina@fc.up.pt and Centre for Mechanical Technology and Automation (TEMA), Department of Mechanical Engineering, University of Aveiro, 3810-193, Aveiro, Portugal and IFIMUP-IN and Faculty of Sciences, University of Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal.
Abstract:
Hybrid conjugates of graphene with metallic/semiconducting nanostructures can improve the sensitivity of electrochemical sensors due to their combination of well-balanced electrical/electrocatalytic properties and superior surface-to-volume ratio. In this study, the synthesis and physical characterization of a hybrid conjugate of reduced graphene oxide and nickel nanoparticles (rGO-Ni NPs) is presented. The conjugate was further deposited onto a glassy carbon electrode as a nanocomposite film of chitosan and glucose oxidase. The electrochemical response and morphology of the films were investigated using SEM, CV, and EIS, and their applications as a glucose biosensor explored for the first time in proof-of-concept tests. The low operating potential along with the good linearity and sensitivity (up to 129 μA cm(-2) mM(-1)) found in the sub-millimolar range suggest potential applications in the self-management of hypoglycemia from blood samples or in the development of non-invasive assays for body fluids such as saliva, tears or breath.
