Fabrication of Electrochemical Sensor Modified with Porous Graphene for Determination of Trace Calycosin

Abstract In this study, the porous graphene (PG) with excellent structure was successfully prepared by a simple pyrolysis process, and applied to construct electrochemical sensor (PG@GCE) for detection of calycosin (CYS). PG was characterized by Raman spectroscopy, Fourier transform infrared spectroscopy and scanning electron microscopy. Also, the electrochemical properties of the proposed sensors were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), and the results indicated that sensors had relatively large specific surface area and higher electron transport rate. Based on all those characteristics, CYS, a traditional Chinese medicine (TCM) active ingredient, displayed a great response on the surface of PC@GCE. Under the optimized conditions, the sensors displayed a good linear relationship between the peak current and the CYS concentration in the range of 1.8 × 10 –7 –4.4 × 10 –5 M with the detection limit of 5.8 × 10 –8 M ( S/N = 3). This study provided a novel analytical method for detection of CYS, rapid identification of Radix Hedysari and Radix Astragali , and gave another way for the trace analysis of CYS in biological samples. Furthermore, it would also deepen the application of PG in the field of pharmaceutical analysis.