Eco-Friendly Electrochemical Biosensor based on Sodium Carboxymethyl Cellulose/Reduced Graphene Oxide Composite

Reduced graphene oxide (GO) and carboxymethyl cellulose sodium (CMC) composite film was prepared by a simple solution blending method. The obtained composite film was used to modify glassy carbon electrode (GCE) to detect Vitamin B₆ (VB₆) with electrochemical measurements. Morphologies and stucture of the composite were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR) and electron paramagnetic resonance (EPR). The electrochemistry performances of the GCE modified by GO/CMC composite were investigated by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The results revealed that CMC and GO were able to form a homogeneous mixture, and the modified GCE presented extremely strong sensitivity towards VB₆ such as high detection sensitivity, low detection limit, small Ret value, certain stability and excellent reversibility. The good performance might be attributed to high electrical conductivity and large surface-to-volume ratio of GO which could accelerate electron transfer between the surface of GCE and VB₆. The test results showed that GO/CMC composite was a novel electrochemical biosensor for the detection of VB₆. [Figure not available: see fulltext.].