Highly Selective and Sensitive Determination of Dopamine in the Presence of Ascorbic Acid Using a 3D Graphene Foam Electrode

A three-dimensional (3D), macroporous and highly conductive graphene foam (GF) was synthesized by atmospheric pressure chemical vapor deposition (CVD). The morphologies of the GF were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The structure of the GF was investigated by X-ray diffraction (XRD) and Raman spectroscopy. The GF prepared by CVD was then transferred onto ITO coated glass, acting as an electrode, to detect dopamine (DA) and ascorbic acid (AA) by electrochemical methods. The results show that the GF exhibits high selectivity for the detection of DA and AA. It also shows high sensitivity for detection of DA with the lower detection limits of similar to 2.0 nM in the linear response up to similar to 10 mu M. This demonstrates the free-standing GF provides a promising platform as a 3D biosensing material.