Ultracentrifugation-polyanion precipitation

Ultracentrifugation at density 1.006Kg/L to float VLDL Precipitation with polyanion/cation for HDL LDL calculated as density >1.006 - HDL Most cornmonly used by specialty lipid laboratories... 

For separation and quantitation of human serum lipoproteins, several technics are currently used. These technics include preparative ultracentrifugation (1-3), gel filtration (1,4), selective precipitation with polyanion/divalent cation reagents (1,5), electrophoresis (1,6), affinity choromatography (7), and ultrafiltration (8). For effective separation of all major lipoprotein classes, a combination procedure consisting of several technics above mentioned is frequently used. Therefore, this leads to difficulties, that is, the loss and alteration or decomposition of lipoprotein components due to time consuming experimental procedures. ... 

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