Saccharose-Epichlorhydrin-Copolymer Komponenten

Ficoll is a neutral, highly branched, high-mass,

hydrophilic A hydrophile is a molecule or other molecular entity that is attracted to water molecules and tends to be dissolved by water.Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon'' Oxford: Clarendon Press. In contrast, hydrophobes are n ...

polysaccharide Polysaccharides (), or polycarbohydrates, are the most abundant carbohydrates found in food. They are long chain polymeric carbohydrates composed of monosaccharide units bound together by glycosidic linkages. This carbohydrate can react with w ...

which dissolves readily in

aqueous An aqueous solution is a solution in which the solvent is water. It is mostly shown in chemical equations by appending (aq) to the relevant chemical formula. For example, a solution of table salt, or sodium chloride (NaCl), in water would be re ...

solution Solution may refer to: * Solution (chemistry), a mixture where one substance is dissolved in another * Solution (equation), in mathematics ** Numerical solution, in numerical analysis, approximate solutions within specified error bounds * Solutio ...

s. Ficoll radii range from 2-7 nm. It is prepared by reaction of the polysaccharide with

epichlorohydrin Epichlorohydrin (abbreviated ECH) is an organochlorine compound and an epoxide. Despite its name, it is not a halohydrin. It is a colorless liquid with a pungent, garlic-like odor, moderately soluble in water, but miscible with most polar organ ...

. Ficoll is a registered trademark owned by GE Healthcare companies. Ficoll is part of Ficoll-Paque, which is used in

biology Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary ...

laboratories A laboratory (; ; colloquially lab) is a facility that provides controlled conditions in which scientific or technological research, experiments, and measurement may be performed. Laboratory services are provided in a variety of settings: physi ...

to separate

blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the cir ...

to its components (

erythrocyte Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "hol ...

leukocyte White blood cells, also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from mult ...

s etc.). Ficoll-Paque is normally placed at the bottom of a conical tube, and blood is then slowly layered above Ficoll-Paque. After being

centrifuge A centrifuge is a device that uses centrifugal force to separate various components of a fluid. This is achieved by spinning the fluid at high speed within a container, thereby separating fluids of different densities (e.g. cream from milk) or ...

d, the following layers will be visible in the conical tube, from top to bottom: plasma and other constituents, a layer of mono-nuclear cells called

buffy coat The buffy coat is the fraction of an anticoagulated blood sample that contains most of the white blood cells and platelets following centrifugation. It is rich in a number of immune cells including leukocytes, granulocytes. Description Aft ...

(

PBMC A peripheral blood mononuclear cell (PBMC) is any peripheral blood cell having a round nucleus. These cells consist of lymphocytes (T cells, B cells, NK cells) and monocytes, whereas erythrocytes and platelets have no nuclei, and granulocytes ( ...

/MNC), Ficoll-Paque, and erythrocytes &

granulocytes Granulocytes are cells in the innate immune system characterized by the presence of specific granules in their cytoplasm. Such granules distinguish them from the various agranulocytes. All myeloblastic granulocytes are polymorphonuclear. They ha ...

which should be present in pellet form. This separation allows easy harvest of PBMCs. Note that some

red blood cell Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "hol ...

trapping (presence of erythrocytes & granulocytes) may occur in the PBMC or Ficoll-Paque layer. Major

blood clotting Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It potentially results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The mechan ...

may sometimes occur in the PBMC layer. Ethylene diamine tetra-acetate (

EDTA Ethylenediaminetetraacetic acid (EDTA) is an aminopolycarboxylic acid with the formula H2N(CH2CO2H)2sub>2. This white, water-soluble solid is widely used to bind to iron (Fe2+/Fe3+) and calcium ions (Ca2+), forming water-soluble complexes ev ...

) and heparin are commonly used in conjunction with Ficoll-Paque(TM) to prevent clotting and is used as a mononuclear cell separator. At one time, fairly early in the research for diabetes treatment by transplantation, Ficoll was used in an attempt to separate

islets of Langerhans The pancreatic islets or islets of Langerhans are the regions of the pancreas that contain its endocrine (hormone-producing) cells, discovered in 1869 by German pathological anatomist Paul Langerhans. The pancreatic islets constitute 1–2% of ...

from enzyme (collagenase) digested human pancreatic tissue. The theory was that separated islets could then be used for transplantation into patients with

type 1 diabetes Type 1 diabetes (T1D), formerly known as juvenile diabetes, is an autoimmune disease that originates when cells that make insulin (beta cells) are destroyed by the immune system. Insulin is a hormone required for the cells to use blood sugar f ...

. In practice, using Ficoll led to difficulty obtaining a pure enough preparation of islets, with enough islet recovery from the original tissue, for safe and effective islet transplantation in humans. Because Ficoll-Paque layering is a very slow process, devices that aid in the most time-consuming step, the overlay, have been developed. One such product is SepMate-50, a specialized tube containing a porous insert that forms a physical barrier between the Ficoll-Paque and blood sample. This allows the blood sample to be rapidly pipetted onto the insert, avoiding the need for overlaying it directly onto Ficoll-Paque. The SepMate insert also reduces the duration of the centrifugation step, and after centrifugation, the top layer containing plasma and PBMCs can be poured into a new tube. Other devices include a column containing a porous high-density

polyethylene Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging ( plastic bags, plastic films, geomembranes and containers including b ...

barrier or "frit." 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. The cost of this product is significantly higher than basic Ficoll and Ficoll-Paque products. It is also possible to have the Ficoll-Paque separating system included in the

Vacutainer A vacutainer blood collection tube is a Sterilization (microbiology), sterile glass or plastic test tube with a colored rubber stopper creating a vacuum seal inside of the tube, facilitating the drawing of a predetermined volume of liquid. Vacut ...

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

External links

Cell Separation Media, Methodology & Applications Handbook
{{Webarchive, url=https://web.archive.org/web/20081205061748/http://www.gelifesciences.com/handbooks , date=2008-12-05 Cell culture reagents Polysaccharides

See also

Notes

External links