Scalable fabrication of graphene-assembled multifunctional electrode with efficient electrochemical detection of dopamine and glucose

Conventional glassy carbon electrodes(GCE)cannot meet the requirements of future electrodes for wider use due to low conductivity,high cost,non-portability,lack of flexibility.Therefore,cost-effective and wearable electrode enabling rapid and versatile molecule detection is becoming important,especially with the ever-increasing demand for health monitoring and point-ofcare diagnosis.Graphene is considered as an ideal electrode due to its excellent physicochemical properties.Here,we prepare graphene film with ultra-high conductivity and customize the 3-electrode system via a facile and highly controllable laser engraving approach.Benefiting from the ultra-high conductivity(5.65×10^(5)S·m^(−1)),the 3-electrode system can be used as multifunctional electrode for direct detection of dopamine(DA)and enzyme-based detection of glucose without further metal deposition.The dynamic ranges from 1–200μM to 0.5–8.0 mM were observed for DA and glucose,respectively,with a limit of detection(LOD)of 0.6μM and 0.41 mM.Overall,the excellent target detection capability caused by the ultra-high conductivity and ease modification of graphene films,together with their superb mechanical properties and ease of mass-produced,provides clear potential not only for replacing GCE for various electrochemical studies but also for the development of portable and highperformance electrochemical wearable medical devices.