UNIT 20.7 Analytical Ultracentrifugation: Sedimentation Velocity Analysis

  1. Walter Stafford1,2

Published Online: 1 MAY 2003

DOI: 10.1002/0471140864.ps2007s31

Current Protocols in Protein Science

Current Protocols in Protein Science

How to Cite

Stafford, W. 2003. Analytical Ultracentrifugation: Sedimentation Velocity Analysis. Current Protocols in Protein Science. 31:20.7:20.7.1–20.7.11.

Author Information

  1. 1

    Analytical Ultracentrifugation Research Laboratory Boston Biomedical Research Institute, Watertown, Massachusetts

  2. 2

    Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts

Publication History

  1. Published Online: 1 MAY 2003
  2. Published Print: FEB 2003


The analytical ultracentrifuge is a high speed centrifuge with an optical system allowing observation of the concentration of macromolecules as a function of radius and time. In sedimentation velocity experiments,relatively high speeds are used so that a boundary is formed between the solution of sedimenting macromolecule and the buffer in which it is dissolved. Analysis of the rate boundary movement and evolution of its shape can yield information about the molar masses of species present as well as stoichiometries and equilibrium constants for their interactions. This overview discusses crucial issues pertaining to sedimentation velocity experiments, including non-interacting and interacting systems, ideality and non-ideality, and reversible versus kinetically limited equilibrium scenarios.