Ferrocene-functionalized graphene electrode for biosensing applications

• A novel ferrocene-functionalized reduced graphene oxide based electrode.
• Ease of preparation by drop-casting of Fc-modified graphene and chitosan mixture.
• Well-defined and exploitable ferrocene CV signal for sensing purposes.
• Sensitive enzymeless detection of hydrogen peroxide at low potentials.
• Enzymatic Sensitive detection of glucose on GOx-modified graphene electrode.

A novel ferrocene-functionalized reduced graphene oxide (rGO)-based electrode is proposed. It was fabricated by the drop casting of ferrocene-functionalized graphene onto polyester substrate as the working electrode integrated within screen-printed reference and counter electrodes. The ferrocene-functionalized rGO has been fully characterized using FTIR, XPS, contact angle measurements, SEM and TEM microscopy, and cyclic voltammetry. The XPS and EDX analysis showed the presence of Fe element related to the introduced ferrocene groups, which is confirmed by a clear CV signal at ca. 0.25 V vs. Ag/AgCl (0.1 KCl). Mediated redox catalysis of H2O2 and bio-functionalization with glucose oxidase for glucose detection were achieved by the bioelectrode providing a proof for potential biosensing applications.

An easy-to-prepare standalone graphene electrode was obtained by the drop-casting ferrocene-functionalized rGO on PET polymer. This electrode can be used as an enzymeless electrochemical sensor for the detection of hydrogen peroxide or as an amperometric enzyme-based biosensor for sensitive glucose detection.Figure optionsDownload as PowerPoint slide