Development of an Electrodeposited Graphene Quantum Dot Electrode for the Electrochemical Detection of C‐Reactive Protein (CRP) Biomarker

Abstract

AbstractC‐reactive protein (CRP) is a potential cardiac biomarker whose levels fluctuate in response to cardiac diseases. In particular, the severity of cardiovascular disease can be associated with the level of CRP, emphasizing the necessity for a highly sensitive biosensor capable of detecting CRP at ultralow levels in a short period of time. In this study, we used a facile pyrolysis method to synthesize graphene quantum dots (GQDs) with a diameter of 2.2 nm. Then, to fabricate the Au/GQDs/anti‐CRP electrode, GQDs were electrodeposited successfully on the surface of the bare Au electrode to provide a nano‐interfaced matrix platform for effective anti‐CRP immobilization. Cyclic voltammetry was used to investigate the contact between anti‐CRP and CRP in the Fe(CN)63−/4− as a mediator. The recorded current signal from differential pulse voltammetry measurements shows that the associative interaction between the anti‐CRP and CRP is efficiently induced. Furthermore, the Figureure of merits of the developed sensor, including the sensory response of <50 s with a high sensitivity of 58 μA ng−1 mL−1 cm−2 and a low detection capability of 0.104 ng mL−1 (n=3), suggests that it is a potential candidate for point‐of‐care testing. And the fabricated Au/GQDs/anti‐CRP biosensor were used to sense CRP in an artificial serum (ringer lactate) solution.