title: Atomic force microscopy applied to study macromolecular content of embedded biological material.
abstract: We demonstrate that atomic force microscopy represents a powerful tool for the estimation of structural preservation of biological samples embedded in epoxy resin, in terms of their macromolecular distribution and architecture. The comparison of atomic force microscopy (AFM) and transmission electron microscopy (TEM) images of a biosample (Caenorhabditis elegans) prepared following to different types of freeze-substitution protocols (conventional OsO4 fixation, epoxy fixation) led to the conclusion that high TEM stainability of the sample results from a low macromolecular density of the cellular matrix. We propose a novel procedure aimed to obtain AFM and TEM images of the same particular organelle, which strongly facilitates AFM image interpretation and reveals new ultrastructural aspects (mainly protein arrangement) of a biosample in addition to TEM data.
authors.affiliation: Electron Microscopy Centre, Institute of Applied Physics, HPM C 15.1, ETH-Hoenggerberg, CH-8093, Zuerich, Switzerland. matsko@iap.phys.ethz.ch
authors.forename: Nadejda B
authors.initials: NB
authors.lastname: Matsko
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000737:chemistry / Q000648:ultrastructure*; D029742:Caenorhabditis elegans Proteins / Q000032:analysis*; D004853:Epoxy Resins; D017110:Freeze Substitution; D018625:Microscopy, Atomic Force / Q000379:methods*; D046529:Microscopy, Electron, Transmission; D016610:Tissue Embedding
chemical_list: D029742:Caenorhabditis elegans Proteins; D004853:Epoxy Resins