Analytical ultracentrifugation

Analytical ultracentrifugation (AUC) is a biochemical technique that measures the sedimentation behavior of macromolecules in solution. This technique is used to determine the size, shape, and interaction of macromolecules, which can provide important information about their structure and function.

History

Analytical ultracentrifugation was first developed in the 1920s by Theodor Svedberg, who was awarded the Nobel Prize in Chemistry in 1926 for his work on the technique. Since then, AUC has been used in a wide range of scientific fields, including biochemistry, molecular biology, and polymer science.

Principle

The principle of analytical ultracentrifugation is based on the sedimentation of macromolecules in a centrifugal field. When a solution of macromolecules is subjected to high centrifugal forces, the macromolecules move towards the bottom of the centrifuge tube at a rate that depends on their size, shape, and density. By measuring the rate of sedimentation, it is possible to determine the physical properties of the macromolecules.

Techniques

There are two main techniques used in analytical ultracentrifugation: sedimentation velocity and sedimentation equilibrium.

Sedimentation velocity measures the rate at which macromolecules move through a solution under the influence of centrifugal force. This technique is used to determine the size and shape of macromolecules.

Sedimentation equilibrium measures the concentration of macromolecules at equilibrium under the influence of centrifugal force. This technique is used to determine the molecular weight of macromolecules.

Applications

Analytical ultracentrifugation has a wide range of applications in the field of biochemistry and molecular biology. It is used to study the size and shape of macromolecules, their interactions with other molecules, and their assembly into larger complexes. AUC is also used in the study of protein folding, protein aggregation, and the formation of protein-nucleic acid complexes.

See also

• Centrifugation
• Sedimentation coefficient
• Theodor Svedberg