Monitoring of peptide induced disruption of artificial lipid membrane constructed on boron-doped nanocrystalline diamond by electrochemical impedance spectroscopy

Abstract

With the rise of antibiotic resistance of pathogenic bacteria there is an increased demand for monitoring of the functionality of bacteria membranes, whose disruption can be induced by peptide lipid interactions. In this work we attempt to monitor formation and subsequent peptide induced disruption of supported lipid membranes (SLBs) on boron-doped nanocrystalline diamond (B-NCD). Electrochemical Impedance Spectroscopy (EIS) was used to study in situ changes related to lipid membrane formation and disruption by peptide-induced interactions. The observed impedance changes were minimal for oxidized B-NCD samples. The sensitivity for the detection of membrane formation and disruption was significantly higher for hydrogenated B-NCD surfaces. Data modelling indicates large differences in the structure of electrical double layer at the B-NCD/SLB interface for hydrogen and oxygen terminated B-NCD surfaces. For oxidized B-NCD surfaces, EIS changes are negligible. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim