An Electrochemical Sensor Based on Reduced Graphene Oxide Modified Carbon Paste Electrode for Curcumin Determination in Human Blood Serum

A sensitive, accurate electrochemical sensor based on reduced graphene oxide modified carbon paste electrode (RGO/CPE) was developed to m easure curcumin levels in human blood serum. The as-prepared electrode (RGO/C PE) was verified to outperform bare carbon paste electrode (CPE), with increased o xidation and reduction peaks at +0.505 V and +0.408 V, respectively. Curcumin measu rement was performed using cyclic voltammetry (CV) and differential pulse volt ammetry (DPV) techniques. RGO/CPE showed a desirable linear response towards curcumin, within the concentration range of 10-6000 μM; the detection li mit (S/N = 3) was 3.183 μM. Moreover, electrochemical impedance spectroscopy (E IS) and field emission scanning electron microscope (FESEM) were applied to gain fu rther insight into the electrochemical behavior of the proposed electrode. Th results revealed that the usage of RGO caused increased sensitivity of the sensor r esponse to curcumin; therefore, RGO/CPE can be considered a promising electrochemic al sensor for curcumin determination in human blood serum.