Amyloid-beta (A beta) peptides are important and reliable molecular biomarkers for the diagnosis and prognosis of Alzheimer's disease. Aggregation and fibrillation of A beta peptides on ganglioside GM1 (GM1)-containing lipid membranes is considered a cause of neurodegenerative disease. Because GM1 is abundant in the central nervous system and plays a key role in the aggregation of A beta, the interaction of A beta with supported planar lipid bilayers (SPBs) containing GM1 is of great significance. We prepared SPBs containing GM1 in order to study the electrochemical characteristics of GM1/sphingomyelin/cholesterol SPBs and their interaction with A beta(1-40) by cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The results suggested that SPBs formed an insulating layer on the surface of the electrode and were damaged by A beta(1-40), thereby reducing the resistance of SPBs and enhancing the capacity and rate of ion transport. The results obtained from EIS correlated well with Thioflavin T fluorescence and atomic force microscopy, which proved that EIS is a promising method for analyzing the interaction between A beta peptides and lipid membranes. (C) 2015 The Electrochemical Society.