Protein Crystallography and Biophysics Centre (BiophysX)
Institute of Structural and Molecular Biology (ISMB)
Birkbeck College / University College London

Analytical Ultracentrifugation
(Beckman XL-I)

AUC_photo Analytical Ultra-Centrifugation (AUC) is the method of choice for determination of the molecular weight of macromolecular complexes (from small polypeptides to viruses) under native solution conditions. The radial distribution of protein in the spinning cell, that arises from the action of both the outward centrifugal force and random diffusion, is mass (in a sedimentation equilibrium experiment) or mass and shape dependent (in a sedimentation velocity experiment). Numerical analysis of data can determine even very weak association constants and reveal the size distributions of solutions containing multiple species.

Our Beckman XL-I has absorption as well as interference optics able to observe sedimenting species under a wide range of buffer conditions and concentrations.

Please note that the AUC, while available, is not completely supported by the facility. We can however accommodate specific experiments under request.

Beckman site
EMBL site including protocols
Protocol in jove

ISMB Protein Crystallography and Biophysics Centre, Birkbeck, University of London
Last modified April 2021