title: Vertical dimension of hydrated biological samples in tapping mode scanning force microscopy.
abstract: The vertical dimensions of the well-characterized test samples tobacco mosaic virus, T4 bacteriophage polyhead, purple membrane, and hexagonally packed intermediate (HPI) layer were investigated by tapping mode scanning force microscopy (SFM) in solution. Purple membrane and HPI layer were imaged in both contact mode and tapping mode SFM for direct comparison. All vertical dimensions match the known heights. The practical implications of the absence of frictional forces in tapping mode are discussed.
authors.affiliation: Humboldt University of Berlin, Department of Physics, Germany. schabert@physik.hu-berlin.de
authors.forename: F A
authors.initials: FA
authors.lastname: Schabert
authors.forename: J P
authors.initials: JP
authors.lastname: Rabe
mesh_terms: D017122:Bacteriophage T4 / Q000648:ultrastructure; D055592:Biophysical Phenomena; D001703:Biophysics; D005069:Evaluation Studies as Topic; D006108:Graphite; D046911:Macromolecular Substances; D018625:Microscopy, Atomic Force / Q000379:methods*; D018717:Purple Membrane / Q000648:ultrastructure; D014027:Tobacco Mosaic Virus / Q000648:ultrastructure; D014867:Water
chemical_list: D046911:Macromolecular Substances; D014867:Water; D006108:Graphite