TwinSpin centrifugation tubes can be used for density-based separation of particles. The TwinSpin is comprised of a standard 15 ml and an inner tube. The inner tube has an open bottom which is submersed in the Density Gradient Medium (DGM). The sample can simply be pipetted into the TwinSpin. The sample lays on top of the DGM inside the inner tube. During centrifugation the particle mixture gets separated according their specific density. The result depends on the separation goal. The targets can be enriched is the inter-phase above the DGM. On top of the interphase will be particles of a lower specific density or micro-particles. Unwanted particles with a higher specific density will sediment out of the inner tube and concentrated on the bottom of the outer tube. TwinSpin can also be used for the removal of lower density particles or micro-particles from the sample. The target particles will now be concentrated on the bottom of the outer tube and the unwanted debris will stay inside the inner tube. After centrifugation the inner tube will be apart from the outer tube and disposed in case the targes are in the outer tube or emptied drop by drop by using the device like a pipette.bottom of the outer tube. When separation is complete, just remove the inner tube. The elastic cap functions as valve. By pushing the cap down, the collection tube becomes a pipette. The contents can be collected drop by drop. Prefilled with DGM of your choice.