title: Monitoring single-molecule reactivity on a carbon nanotube.
abstract: Using point-functionalized carbon nanotube devices, we demonstrate continuous, multihour monitoring of a single carboxylate group interacting with its immediate environment. The conductance of the nanotube device directly transduces single-molecule attachments and detachments in the presence of the carboxylate-selective reagent 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC). Because only one carboxylate is present in the device, it can be studied through hundreds of reactions, providing the statistical accuracy to directly determine a 12 s lifetime of the carboxy-EDC complex. An additional instability of the complex is transduced in real time and observed to have a median lifetime of 2 ms. By determining a turnover time in good agreement with bulk measurements and simultaneously illuminating additional dynamics, these results demonstrate this platform's potential for complementing optical methods in single-molecule research.
authors: Departments of Physics and Astronomy, Molecular Biology and Biochemistry, and Chemistry, University of California, Irvine, California 92697-2025, USA.
authors: Brett R
authors: BR
authors: Goldsmith
authors: John G
authors: JG
authors: Coroneus
authors: Alexander A
authors: AA
authors: Kane
authors: Gregory A
authors: GA
authors: Weiss
authors: Philip G
authors: PG
authors: Collins