Conductance Titration of Single-Peptide Molecules

摘要: We have measured the conductance of single peptides covalently bonded to two Au electrodes via S−Au bonds by repeatedly forming a large number molecular junctions. The decreases exponentially with peptide length, decay constant β = 0.9 ± 0.1 A-1, suggesting that tunneling is mechanism electron transport in peptides. sensitive solution pH, due protonation/deprotonation amine and carboxyl groups peptides, which provides titration measurements based on single-molecule conductance.