Conductance Titration of Single-Peptide Molecules

摘要

The ability to measure the conductance of a single molecule wired to two electrodes is a basic requirement toward electronic devices based on single molecules.1-11 It also promises a fresh approach to study various chemical processes and reactions on a single-molecule basis by simply monitoring the conductance of the molecule. We report here a study of electron transport in single peptides covalently bonded to two electrodes. By monitoring the pH dependence of the peptide conductance, we provide the first conductance titration measurement of a single molecule. We chose peptides because they are the building blocks of proteins, in which electron transport is directly relevant to many biological functions.