Probing biomimetic molecular structures on gold and silicon(111) with electrical impedance spectroscopy

Abstract

Self-assembled monolayers (SAMs) offer an approach for engineering molecular interfaces that mimic biological structures and their processes on solid substrates. Here we demonstrate the ability of electrical impedance spectroscopy to monitor the biological process of DNA recognition in a monolayer comprised of single stranded DNA assembled on a gold substrate and characterize the structure of a hybrid bimolecular lipid membrane (BLM) on an atomically flat silicon surface. These biomimetic examples demonstrate the crucial importance of the impedance phase in being able to distinguish between electrical conductive and capacitive properties of the molecular interfaces. © Springer-Verlag 2007.