Electrochemical determination of mangiferin and icariin based on Au-AgNPs/MWNTs-SGSs modified glassy carbon electrode

A novel Au-Ag nanoparticles (NPs) on multi-walled carbon nanotubes/sulfonated graphene sheets modified glassy carbon electrode (Au-AgNPs/MWNTs-SGSs/GCE) was prepared to determine mangiferin (MIN) and icariin (IIN) by electrochemical methods Scanning electron microscopy and energy-dispersive spectroscopy showed that Au-AgNPs were electrodeposited on drape and tubular structure of MWNTs-SGSs/GCE successfully. The modified electrode had high electroactivities against both MIN and IIN. The anodic peak currents of MIN and IIN on the GCE modified by Au-AgNPs/MWNTs-SGSs were much higher than those on the bare GCE. Differential pulse voltammetry showed a wide detection range of 0.05   ∼   500.0   μM for MIN and 0.05   ∼   100.0   μM for IIN, with low detection limits (0.017   μM both) as well as high sensitivity, selectivity and repeatability. Au-AgNPs/MWNTs-SGSs/GCE was successfully applied to simultaneously detect MIN and IIN in Rhizoma anemarrhenae and to independently determine MIN in Artemisia capillaris Herba and IIN in the leaves of Epimedium macranthum .