Ultracentrifugáció

Ultracentrifugáció (ultracentrifugation) is a laboratory technique used to separate components of a mixture based on their size and density. It utilizes a centrifuge that spins at extremely high speeds, generating centrifugal forces far greater than those produced by standard centrifuges. These forces cause particles of different densities and sizes to sediment at different rates.

The process involves placing a sample in a tube and spinning it in an ultracentrifuge rotor. The rotor's speed can range from tens of thousands to hundreds of thousands of revolutions per minute (rpm). The resulting high centrifugal field forces denser or larger particles to move towards the bottom of the tube more quickly than lighter or smaller particles. This differential sedimentation leads to the separation of components into distinct layers within the tube.

There are two main types of ultracentrifugation: analytical and preparative. Analytical ultracentrifugation is primarily used to determine the physical properties of macromolecules, such as their molecular weight, shape, and aggregation state. Preparative ultracentrifugation, on the other hand, is used to isolate and purify specific components from a mixture. This can include separating proteins, nucleic acids, viruses, or cellular organelles.

The technique requires specialized equipment and careful handling of samples due to the high speeds involved. Ultracentrifugation is a powerful tool in biochemistry, molecular biology, and cell biology for research and purification purposes. It allows for the characterization and isolation of delicate biological molecules that might be damaged by other separation methods.