Single-molecule Fluorescence and Force Microscopy Employing Carbon Nanotubes
Lawrence A. Wade, Ian Shapiro, Ziyang Ma, Stephen R. Quake, Charles Patrick Collier
California Institute of Technology, US
Keywords: Atomic Force Microscopy, Single-Wall Nanotubes, Molecular Dynamics
The observation of spectroscopic signals, in response to mechanically induced changes in biological macromolecules can be enabled at an unprecedented level of resolution by coupling single-molecule manipulation/sensing using carbon nanotubes with single-molecule fluorescence imaging. Proteins, DNA and other biomolecules can be attached to the nanotubes to give highly specific single-molecule probes for the investigation of intermolecular dynamics, the assembly of hybrid biological and nanoscale materials and the development of nanoscale circuitry. Despite the great promise of these tools, there has been little success throughout the community in employing them to conduct broad measurements primarily because of the difficulty in reproducibly and easily producing large quantities of single-walled nanotube AFM tips.
We are developing generalized techniques for the growth and attachment of SWNTs for AFM imaging, to serve as the foundation of an effort to develop single-molecule sensors on nanotube AFM tips for a hybrid atomic force microscope that also has single-molecule fluorescence imaging capability. We are achieving typical resolutions of 5-6 nm (FWHM ? SWNT diameter) when AFM imaging with SWNT tips. The resolution is approximately 40% better than can be achieved with the best conventional silicon tips and more than a factor of two better than normal silicon AFM tips.
NSTI Nanotech 2003 Conference Technical Program Abstract