Biomaterial Database

The isolation of lipoproteins from human plasma by ultracentrifugation in zonal rotors. 1971

H G Wilcox, and D C Davis, and M Heimberg

The major classes of lipoproteins were isolated from human plasma by ultracentrifugation in continuous density gradients using the Ti-14 and Ti-15 zonal rotors. Chylomicrons + VLDL, LDL, and HDL were separated from each other and from the more dense residual proteins (albumin fraction) of plasma by rate-zonal flotation in NaBr gradients in the density range 1.0-1.4. The chylomicron-VLDL fraction was subfractionated into constituent chylomicrons and VLDL by zonal ultracentrifugation in NaBr gradients in the density range 1.0-1.1. Plasma lipoproteins were analyzed for composition of lipids and content of protein, for electrophoretic mobility on paper, and for antigenic determinants by immunoelectrophoresis and immunodiffusion. Flotation constants (S(f)) of the LDL and HDL were calculated from measurements made in the analytical ultracentrifuge. Lipoproteins isolated from plasma by zonal ultracentrifugation were identical by these criteria to lipoproteins isolated by the usual procedure of sequential ultracentrifugation in solvents of increasing density. The procedure of zonal ultracentrifugation is rapid, quantitative, and less laborious than sequential techniques. Lipoproteins isolated by zonal ultracentrifugation are relatively uncontaminated by other proteins and extensive washing is therefore unnecessary. Zonal ultracentrifugation is more than a preparative method for the plasma lipoproteins; it is also an analytical procedure in that a record is obtained of the distribution and quantity of the lipoprotein within the continuous density gradient.

UI	MeSH Term	Description	Entries
D007106	Immune Sera	Serum that contains antibodies. It is obtained from an animal that has been immunized either by ANTIGEN injection or infection with microorganisms containing the antigen.	Antisera,Immune Serums,Sera, Immune,Serums, Immune
D007122	Immunoelectrophoresis	A technique that combines protein electrophoresis and double immunodiffusion. In this procedure proteins are first separated by gel electrophoresis (usually agarose), then made visible by immunodiffusion of specific antibodies. A distinct elliptical precipitin arc results for each protein detectable by the antisera.
D008074	Lipoproteins	Lipid-protein complexes involved in the transportation and metabolism of lipids in the body. They are spherical particles consisting of a hydrophobic core of TRIGLYCERIDES and CHOLESTEROL ESTERS surrounded by a layer of hydrophilic free CHOLESTEROL; PHOSPHOLIPIDS; and APOLIPOPROTEINS. Lipoproteins are classified by their varying buoyant density and sizes.	Circulating Lipoproteins,Lipoprotein,Lipoproteins, Circulating
D008722	Methods	A series of steps taken in order to conduct research.	Techniques,Methodological Studies,Methodological Study,Procedures,Studies, Methodological,Study, Methodological,Method,Procedure,Technique
D010743	Phospholipids	Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.	Phosphatides,Phospholipid
D001798	Blood Proteins	Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.	Blood Protein,Plasma Protein,Plasma Proteins,Serum Protein,Serum Proteins,Protein, Blood,Protein, Plasma,Protein, Serum,Proteins, Blood,Proteins, Plasma,Proteins, Serum
D002499	Centrifugation, Density Gradient	Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Centrifugations, Density Gradient,Density Gradient Centrifugation,Density Gradient Centrifugations,Gradient Centrifugation, Density,Gradient Centrifugations, Density
D002501	Centrifugation, Zonal	Centrifugation using a rotating chamber of large capacity in which to separate cell organelles by density-gradient centrifugation. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Centrifugations, Zonal,Zonal Centrifugation,Zonal Centrifugations
D002784	Cholesterol	The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.	Epicholesterol
D002914	Chylomicrons	A class of lipoproteins that carry dietary CHOLESTEROL and TRIGLYCERIDES from the SMALL INTESTINE to the tissues. Their density (0.93-1.006 g/ml) is the same as that of VERY-LOW-DENSITY LIPOPROTEINS.	Chylomicron