- Ficoll
Ficoll is a neutral, highly branched, high-mass,
hydrophilic polysaccharide which dissolves readily in aqueoussolution s. Ficoll radii range from 2-7 nm. It is prepared by reaction of the polysaccharide withepichlorohydrin . Ficoll is a registered trademark owned by GE Healthcare companies.cite web |url=http://tess2.uspto.gov/bin/showfield?f=doc&state=r67qfq.2.2 |title=Ficoll |accessdate=2007-02-15 |publisher=United States Patent and Trademark Office]Ficoll is part of Ficoll-Paque which is used in
biology laboratories to separateblood to its components (erythrocyte s,leukocyte s etc.) Ficoll-Paque is a registered trademark owned by GE Healthcare companies. Ficoll-Paque is normally placed at the bottom of a column, and blood is then slowly layered above Ficoll-Paque. After beingcentrifuge d, the following layers will be visible in the column, from top to bottom: plasma and other constituents, a layer of mono-nuclear cells calledbuffy coat (PBMC /MNC), Ficoll-Paque, and erythrocytes &granulocytes which should be present in pellet form. This separation allows easy harvest of PBMC's. Note that somered blood cell trapping (presence of erythrocytes & granulocytes) may occur in the PBMC or Ficoll-Paque layer. Majorblood clotting may sometimes occur in the PBMC layer. Ethylene diamine tetra-acetate (EDTA ) is commonly used in conjunction with Ficoll-Paque(TM) to prevent clotting.Ficoll can also be used to separate
islets of Langerhans from pancreatic tissue. The separated islets can then be used for transplantation into patients withtype 1 diabetes Because Ficoll-Paque layering is a very slow process, similar products which include a column containing a porous high-density
polyethylene barrier or "frit" have been developed. These products allow blood to be layered on much more quickly without mixing polysaccharide and blood. An example of such a product is the "Accuspin System Histopaque-1077" sold by Sigma Aldrich. It is important to note that the cost of these products is significantly higher than basic Ficoll and Ficoll-Paque products. It is also possible to have the Ficoll-Paque separating system included in theVacutainer used to collect the blood. Such vacutainers increase the convenience and safety of collecting blood products, but cost 50 times as much as the basic vacutainer.Notes
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