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Density gradient centrifugation is a method which scientists use to separate intact organelles from a cell. Each type of organelles in a cell has an specific density and based on that density you can separate a certain type of organelle from the others. In In the life sciences, a special technique called density gradient separation is used for isolating and purifying cells, viruses and subcellular particles. Variations of this include Isopycnic centrifugation, Differential centrifugation, and Sucrose gradient centrifugation . A blood donation technique called Pheresis involves density gradient separation. For this type of centrifugation method you may need a refrigerated centrifuge, especially if you are using this for blood work. Not all Density Gradient Centrifugation methods require a refrigerated centrifuge. Some cellular work does not require refrigerated centrifugation. You may be able to use a non refrigerated centrifuge. The Beckman Coulter Centrifuge, Allegra X-12 and Allegra X-12R are refrigerated and non refrigerated models. Again with both of these models you will need to select a rotor and tube adapter separately. Don't forget your centrifuge tubes 2.0ml tubes and 15ml tubes are the most commonly used sizes.

There are three different types of Centrifugal Seperation.The first being Differential centrifugation, which is a common procedure in microbiology and cytology used to separate certain organelles from whole cells for further analysis of specific parts of cells. In the process, a tissue sample is first homogenised to break the cell membranes and mix up the cell contents.The homogenate is then subjected to repeated centrifugations, each time removing the pellet and increasing the centrifugal force. Finally, purification may be done through equilibrium sedimentation,(Sedimentation equilibrium in a solution or suspension of different particles, such as molecules, exists when the rate of transport of each material in any one direction due to sedimentation equals the rate of transport in the opposite direction due to diffusion. Sedimentation is due to an external force, such as gravity or centrifugal force), and the desired layer is extracted for further analysis. For this process you will need a refrigerated centrifuge that has variable speed. Make sure when you are selecting a centrifuge that you confirm if a rotor is included with the centrifuge. Most times the rotor is not included. If not, you will need to select a rotor, and adapter for the specific size centrifuge tubes that you will be using.

"You're traveling through another dimension, Centrifugiation, a dimension not only of sight and sound but of mind; a journey into a wondrous land whose boundaries are that of Scientific imagination. That's the signpost up ahead — your next stop, the Centrifuge Twilight Zone. Centrifugation is a process that involves the use of the centrifugal force for the separation of mixtures, used in industry and in laboratory settings. More-dense components of the mixture migrate away from the axis of the centrifuge, while less-dense components of the mixture migrate towards the axis. Chemists and biologists may increase the effective gravitational force on a test tube so as to more rapidly and completely cause the precipitate ("pellet") to gather on the bottom of the centrifuge tube. The remaining solution is properly called the "supernate" or "supernatant liquid". The supernatant liquid is then either quickly decanted from the tube without disturbing the precipitate, or withdrawn with a Pasteur pipette. The rate of centrifugation is specified by the acceleration applied to the sample, typically measured in revolutions per minute (RPM) or g. The particles' settling velocity in centrifugation is a function of their size and shape, centrifugal acceleration,the volume fraction of solids present, the density difference between the particle and the liquid, and the viscosity. In the chemical and food industries, special centrifuges can process a continuous stream of particle-laden liquid. Portion of credit goes to "Wikipedia"

Another way to get you to buy stuff you don't need. Perpetrators of Live Blood Analysis (LBA) claim they can tell by looking at a slide of your blood just what ails you. Then they proceed to sell you supplements which will take care of these problems. There is no scientific evidence that the problems these "practitioners" claim to identify can be determined by looking at your blood through a microscope. Some practitioners even have the gall to tell people they have cancer, and then "prescribe" supplements which they of course sell. After taking their supplements for a period of time the customers (can't call them patients) are told that they are cured. The trick is to look at the drop of blood on the first visit near the edge of the coverslip where it has already dried somewhat. Then on the subsequest visit, after say 3 months on their supplement, they look at the blood in the middle of the coverslip and proclaim improvement. Customer are of course impressed by an image of their own blood on a computer screen produced by the digital microscope camera. Don't be fooled by scientific sounding phrases like "dark field microscopy", or "enzyme deficiency". Dark field microsopy is a microscopy technique which has been around for many years, not a new discovery. Enzyme deficiency is not a disease unless referring to a specific enzyme and can not be determined by looking at blood. Here is a link to the blog by Stephen Barrett, M.D. where most of this information came from. I urge anyone interested in LBA to Google "live blood analysis fraud"