title: Covalent binding of biological samples to solid supports for scanning probe microscopy in buffer solution.
abstract: Scanning force microscopy allows imaging of biological molecules in their native state in buffer solution. To this end samples have to be fixed to a flat solid support so that they cannot be displaced by the scanning tip. Here we describe a method to achieve the covalent binding of biological samples to glass surfaces. Coverslips were chemically modified with the photoactivatable cross-linker N-5-azido-2-nitrobenzoyloxysuccinimide. Samples are squeezed between derivatized coverslips and then cross-linked to the glass surface by irradiation with ultraviolet light. Such samples can be imaged repeatedly by the scanning force microscope without loss of image quality, whereas identical but not immobilized samples are pushed away by the stylus.
authors.affiliation: Maurice E. Müller-Institute for High-Resolution Electron Microscopy, University of Basel, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Karrasch
authors.forename: M
authors.initials: M
authors.lastname: Dolder
authors.forename: F
authors.initials: F
authors.lastname: Schabert
authors.forename: J
authors.initials: J
authors.lastname: Ramsden
authors.forename: A
authors.initials: A
authors.lastname: Engel
mesh_terms: D001386:Azides; D001704:Biopolymers / Q000032:analysis*; D002021:Buffers; D003432:Cross-Linking Reagents; D007202:Indicators and Reagents; D008853:Microscopy / Q000379:methods*; D012996:Solutions; D013388:Succinimides; D014466:Ultraviolet Rays
chemical_list: D001386:Azides; D001704:Biopolymers; D002021:Buffers; D003432:Cross-Linking Reagents; D007202:Indicators and Reagents; D012996:Solutions; D013388:Succinimides; C049915:N-hydroxysuccinimidyl-5-azido-2-nitrobenzoate