Skip to content
University of Maryland LibrariesDigital Repository at the University of Maryland
    • Login
    View Item 
    •   DRUM
    • Theses and Dissertations from UMD
    • UMD Theses and Dissertations
    • View Item
    •   DRUM
    • Theses and Dissertations from UMD
    • UMD Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Development of Single-Molecule Force and Torque Measurement with Application to Nucleosome Disruption

    Thumbnail
    View/Open
    Chang_umd_0117E_15011.pdf (10.40Mb)
    No. of downloads: 317

    Date
    2014
    Author
    Chang, Jen-Chien
    Advisor
    La Porta, Arthur
    Metadata
    Show full item record
    Abstract
    Single-molecule force spectroscopy is a powerful method in biophysical research. The ability of detecting and manipulating single molecule finds applications in studies from DNA to cell, leads to various mechanism-based results. Among many tools in this field, optical traps is suitable for studies involving nucleic acids and its interaction with protein due to the high temporal and spatial resolution. While most experiments characterize force and displacement, the quest for manipulating and detecting torque and angular motion is increasing due to their significant role in many biological processes. This thesis mainly devotes to the development and application of an optical torque wrench which is capable of simultaneously controlling and measuring force, displacement, torque, and angular displacement of a single bio-molecule. First, angular manipulation of oblate polystyrene particles is demonstrated. Moreover, a new method for fabricating birefringent nanocylinders via nanosphere lithography is presented. Both particles are shown to provide stable angular trapping in a home-built optical torque wrench. We then apply them in measuring a single DNA molecule under force and torque. Mechanical stability of nucleosome under tension and torsion is also studied, followed by a theoretical model to elucidate the importance of torsion in such experiments. Finally, the effect of experimental parameters in a surface-based optical traps on measured kinetics of bio-molecule is detailed.
    URI
    http://hdl.handle.net/1903/15219
    Collections
    • Physics Theses and Dissertations
    • UMD Theses and Dissertations

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility
     

     

    Browse

    All of DRUMCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    LoginRegister
    Pages
    About DRUMAbout Download Statistics

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility