A comparative study on the glucose sensors modified by two different β-cyclodextrin functionalized reduced graphene oxide based Au nanocomposites synthesized through developed post immobilization and in situ growth technologies

Abstract

Graphene based metal nanocomposites are widely used in electrochemical glucose sensors for their prominent synergistic effects. Many reviews have been reported to summarize and compare the two types of synthetic technologies that post immobilization and in situ growth for preparing these nanocomposites. However, these comparisons and evaluations are almost based on the nanomaterials comprised of different components. Based on rationally selecting β-cyclodextrins as the common functional reagents, we have innovatively synthesized two novel graphene based metal nanocomposites composed of the identical ingredients through the developed post immobilization method and new one-step electrodeposition in situ growth approach respectively. After optimized the key parameters to ensure the optimal synthesis conditions were provided, we have further performanced the systematically comparative study on properties of the two nanocomposites from many aspects, so as to scientifically evaluate the two synthesis technologies. Glucose sensors based on the two resultant nanocomposites have been fabricated successfully, both of them showed high response ability. Sensitivity of the sensor modified by the nanocomposite synthesized through in situ growth was improved 3–8 times, demonstrated this strategy is more effective. Our work would provide guidelines to synthesize graphene based metal nanocomposites which has potential applications in electroanalysis.