Cell centrifugal technology.

centrifuges are basic means of studying such as nuclei, mitochondrials, goerkis, lysosomes and microsomes, as well as various macromolecules. It is generally believed that
centrifuges
with a speed of 10 to 25 Kr/min are called high-speed centrifuges; At present, overspeed centrifuges can reach a maximum speed of 100Kr/min and have a centrifugal force of more than 500Kg.
(i), differential centrifugation . Step-by-step centrifuges from low to high speed in media with equal density are used to isolate cells and cells of different sizes.
the order in which the cytocytes sink in differential departure from the heart are: nucleus, mitochondrial, lysosome and peroxidase, endosome and high substate, and finally nuclear protein body.
Because various cells overlap in size and density, and some slow-sink particles are often fast-sinking particles wrapped in sediment blocks, the general effect of repeating 2 to 3 times will be better.
differential centrifuges are only used to isolate cells of varying sizes, and more often for separating cells. The cellular device can be initially separated by differential centrifugation, which often requires further separation and purification through density ladder centrifugation.
velocity gradually increased, the sample by size has precipitated
(ii), density gradient centrifugationwith a certain medium in the
centrifuge tube
to form a continuous or continuous density gradient, cell suspension or plasma medium at the top, through gravity or centrifugal force field effect cell layering, separation. This kind of separation can be divided into velocity subsidon and equal density subsidon balance. The media commonly used for density gradient centrifugation are cesium chloride, sucrose and polysucrose.
media requirements for separating living cells:
1) can produce density gradients, and high density, viscosity is not high;
2) PH neutral or easy to adjust to neutral;
3) concentration when the penetration pressure is small;
4) non-toxic to cells.
A isoveld, B isodulation
1, velocity sedation
velocity seoration is mainly used to isolate cells or cells of varying sizes with similar densities. The medium density used in this method of reduction is low, and the maximum density of the medium should be less than the minimum density of the isolated biological particles.
particles (cells or fine devices) are separated at different speeds according to their respective setoning coefficients in a very flat density gradient medium.
2, iso-density
and other density subsidies are suitable for separating particles with varying densities.
cells or cysts in a continuous gradient medium through enough centrifugal force and long enough to sink or float to the same density as their own media, and stay there to achieve balance, so as to separate different densities of cells or cysts.
density seits are usually performed in higher density media. The maximum density of the medium should be greater than the maximum density of the separated parts, and the gradient of the medium requires a higher steepness and should not be too flat. Moreever, the force field required for this method is usually 10 to 100 times longer than the rate subsidon method, so it often requires high-speed or over-speed centrifugation, and the centrifugal time is also longer. Large centrifugal forces and long centrifugal times are bad for cells.
cells are more susceptible to high centrifugal damage than small cells, and cells that stay in iso-density media suffer greater damage than cells that are on the move. Therefore, this method is suitable for separating cells, not for separating and purifying cells.
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