The purpose of this project is to improve the resolution of the Atomic Force Microscope (AFM). Existing probes for AFMs are relatively blunt at the end (radius of curvature ca. 50 nm), limiting instrumental resolution and making image interpretation difficult when examining macromolecular structures (length scale 1-100 nm). We propose to deposit molecular-scale clusters of controlled size (1-5 nm diameter) on commercially available AFM probes. These clusters will then serve as sharper probe tips. We propose to deposit molecular-scale clusters on flat substrates, which will then serve as test objects to examine the instrumental response function of the AFM. The availability of sharper probe tips and of resolution-testing specimens will aid structural characterization and materials development in a wide range of fields which depend on understanding and/or controlling the function of nanometer-scale structures. In biology and medicine, favorable impacts are expected for studies of: DNA sequences, transmembrane channels, cellular receptors and assemblies of structural polymers, as well as in testing the biocompatibility of various materials. In other disciplines, materials characterization will be aided in studies of catalysis and nanoelectronics.
