Direct Fabrication of 3D Graphene–Multi Walled Carbon Nanotubes Network and Its Application for Sensitive Electrochemical Determination of Hyperin

In this work, pulse potential method (PPM) was proposed to fabricate directly three dimensional graphene (3DG)-multi walled carbon nanotubes (MWCNTs) (3DG-MWCNTs) network on the surface of glassy carbon (GC) electrode in the graphene oxide (GO)-multi walled carbon nanotubes (MWCNTs) (GO-MWCNTs) suspension. GO-MWCNTs and 3DG-MWCNTs were characterized by using scanning electron microscopy (SEM), UV-visible spectrophotometry (UV-vis) and electrochemical experiments. The 3DG-MWCNTs network as a voltammetric material was presented in developing a novel electrochemical sensor for determination of hyperin. Systematic electrochemical tests confirmed that the 3DG-MWCNTs network modified electrode can effectively increase the response to the redox of hyperin, compared with that of bare GC electrode and 3DG network modified electrode. Under the optimal conditions, the response of the sensor demonstrated a linear relationship with hyperin concentration in the range of 5.0 × 10 -9 ~ 1.5 × 10 -6 mol L -1 with a low detection limit of 1.0 × 10 -9 mol L -1 . Moreover, the proposed method showed excellent performance in stability, sensitivity, selectivity and reproducibility for the determination of hyperin.