Improving the cleanliness of graphene grown on copper by chemical vapor deposition for biosensing applications

Since graphene (G) was first isolated by mechanical exfoliation, several methods have been explored for producing G, in order to exploit its extraordinary properties in many applications, including biomedical and biosensing ones. G preparation methods should be selected according to the specific sensing target and mechanism to be utilized, with a balanced consideration on performances (e.g., detection limit and dynamic range), reproducibility, cost and manufacturability. For a wide range of biomedical and biosensing applications, the chemical vapor deposition (CVD) method is considered to be the most promising approach to synthesize large-area, high-quality G, with material properties approaching the theoretical predictions. It is expected that CVD-G will exhibit fascinating electrochemical properties, including wide electrochemical potential windows and low charge-transfer resistance, which can enable the study and exploitation of redox-active biological processes from new perspectives. In our work, we investigate the fabrication of electrochemical biosensors in which G has the role of the transducer and the biosensing element is a redox-active membrane protein embedded in a supported lipid bilayer (SLB) mimicking the cell membrane.