title: Effect of probe force on the resolution of atomic force microscopy of DNA.
abstract: Experimental results are presented to show that the adhesion force is the single most important limiting factor in high-resolution atomic force microscopy of DNA in air, prepared by the cytochrome-C-assisted spreading method. It is also shown that humidity plays a minor role in the control of probe force. Using a pure carbon film as the substrate to clean the AFM tip prior to imaging, it is demonstrated that 4-6 nm resolution on DNA can be routinely obtained by the atomic force microscope with commercial Si3N4 pyramid cantilevers. We also show that in organic solvents a resolution of up to 3 nm can be obtained under optimal conditions.
authors.affiliation: Department of Physiology, University of Virginia, Charlottesville 22908.
authors.forename: J
authors.initials: J
authors.lastname: Yang
authors.forename: Z
authors.initials: Z
authors.lastname: Shao
mesh_terms: D004269:DNA, Bacterial / Q000737:chemistry / Q000648:ultrastructure*; D006813:Humidity; D008854:Microscopy, Electron / Q000295:instrumentation / Q000379:methods*; D010957:Plasmids; D012997:Solvents
chemical_list: D004269:DNA, Bacterial; D012997:Solvents