Here centrifuge manufacturer HUADA introduce you some common Centrifugal Techniques: density gradient centrifugation, analytical centrifugation, differential centrifugation, and Isodensity centrifugation.
The principle of density gradient centrifugation is that molecules settle under centrifugal force until they reach a medium of the same density as they are. The molecules are suspended at a point where the density of the particles is equal to that of the surrounding medium. In this way, molecules of different densities are separated in different layers, which can then be recovered by various processes.
This method was used in the famous experiment which proved that DNA is semi-genetic by using different nitrogen isotopes.
Another example is the use of this technique to separate microsomal fractions from muscle homogenates and then to separate membrane vesicles of different densities.
Analytical centrifugation is a separation method in which the particles in a sample are separated according to their density and the centrifugal force they experience. Analytical ultracentrifugation (AUC) is a versatile and reliable method for the quantitative analysis of large molecules in solution.
Analytical centrifugation can be used to determine the purity of macromolecules. It can also be used to detect changes in the molecular weight of supramolecular complexes. In addition, it can determine the relative molecular mass of solutes in their natural state.
The separation of particles is based entirely on their density and not on their size. The particles move towards the bottom and the movement depends on the size of the particles. And, once the density of the particles becomes equal to the density of the surrounding medium, the flow stops.
As a result, particles with higher densities settle to the bottom, followed by a ribbon-like aggregation above the less dense particles.
Isodensity centrifugation can be used to purify large numbers of biomolecules. It can be used as a technique for determining the density of various particles.
Differential centrifugation is based on the different settling speeds of biological particles of different sizes and densities. The largest class of particles forms a precipitate at the bottom of the centrifuge tube, leaving smaller sized structures in the supernatant. Larger molecules will therefore settle quickly at lower centrifugal forces, while smaller molecules will take longer and require greater forces.
Differential centrifugation is commonly used to separate organelles and cell membranes within cells. It can also be used for low-resolution separation of cell nuclei.
As the technique separates particles according to their size, it can be used to purify extracts containing larger sized impurities.
That's the four usual techniques, hope you can learn some knowledge. Over the years, Hua Da has always focused on the research, development, production and sales of filtration and separation machinery. It not only has a strong technical research centre, but also has established long-term technical cooperation with domestic research institutes, universities and other institutions, and has become the internship base for many universities. You can contact us now to get the centrifuge machines and professional suggestions.
