Reduced graphene oxide-nickel nanoparticles/biopolymer composite films for the sub-millimolar detection of glucose

• Published in: Analyst (London) 2016-06, Vol.141 (13), p.4151-4161
• Main Authors: Krishna, Rahul, Campiña, José M, Fernandes, Paula M. V, Ventura, João, Titus, Elby, Silva, António F
• Format: Article
• Language: English
• Subjects: Biosensing Techniques; Chitosan; Conjugates; Electrodes; Glucose; Glucose - analysis; Glucose Oxidase; Graphene; Graphite; Humans; Linearity; Metal Nanoparticles - chemistry; Nanocomposites; Nanoparticles; Nanostructure; Nickel; Oxides
• ISSN: 0003-2654; 1364-5528
• DOI: 10.1039/c6an00475j

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. A conjugate of reduced graphene oxide and nickel nanoparticles was synthesized and deposited onto GCE as a nanocomposite of chitosan and glucose oxidase. Applications as a glucose biosensor were explored for the first time.