Lultracentrifugació

Ultracentrifugation is a specialized laboratory technique that uses centrifugal forces to separate components of a sample. It achieves significantly higher rotational speeds than traditional centrifuges, often exceeding 100,000 revolutions per minute (rpm). This extreme speed generates very high gravitational forces, enabling the separation of molecules based on subtle differences in size, shape, and density.

The process involves spinning a sample in a rotor at high velocity. The resulting centrifugal force causes denser or larger particles to sediment faster towards the bottom of the sample tube, while less dense or smaller particles remain suspended or sediment more slowly. Different types of ultracentrifuges exist, including preparative ultracentrifuges, which are used to isolate and purify cellular components or macromolecules, and analytical ultracentrifuges, which are employed to study the physical properties of molecules in solution, such as sedimentation velocity and equilibrium.

Applications of ultracentrifugation are widespread in biological and chemical research. It is crucial for isolating organelles like mitochondria and ribosomes from cell homogenates, purifying viruses and proteins, and determining the molecular weight and quaternary structure of macromolecules. The technique is also used in areas such as vaccine development and the study of drug interactions. The design of rotors and the choice of centrifugation medium are critical parameters that influence the separation efficiency and the outcome of the experiment.