Quantification of high-density-lipoprotein cholesterol by precipitation with phosphotungstic acid/MgCl2.
We evaluated the use of a modified phosphotungstic acid/MgCl2 precipitation procedure for the precipitation of apolipoprotein B-containing lipoproteins. Precipitation of these lipoproteins [very-low- and low-density lipoproteins, and lipoprotein (a)] is complete, with negligible coprecipitation of high-density lipoprotein subfractions (HDL1, HDL2, HDL3), even in hypertriglyceridemic sera. In comparison with ultracentrifugation, the precipitation method yields, on the average, values that are 0.17 mmol/L lower for cholesterol values but almost identical for apolipoprotein A-I and phosphatidylcholine. Looking for delta 3,5-cholestadiene formed from cholesterol in the precipitation residue, we used "high-performance" liquid chromatography and "high-performance" thin-layer chromatography and found none.
D001053:Apolipoproteins / Q000302:isolation & purification; D001055:Apolipoproteins B; D011232:Chemical Precipitation; D002774:Cholestadienes / Q000302:isolation & purification; D002784:Cholesterol / Q000097:blood* / Q000302:isolation & purification; D008076:Cholesterol, HDL; D005069:Evaluation Studies as Topic; D006801:Humans; D008075:Lipoproteins, HDL / Q000097:blood* / Q000302:isolation & purification; D008274:Magnesium; D015636:Magnesium Chloride; D010772:Phosphotungstic Acid; D013223:Statistics as Topic; D014280:Triglycerides / Q000097:blood; D014461:Ultracentrifugation
D001053:Apolipoproteins; D001055:Apolipoproteins B; D002774:Cholestadienes; D008076:Cholesterol, HDL; D008075:Lipoproteins, HDL; D014280:Triglycerides; D015636:Magnesium Chloride; D010772:Phosphotungstic Acid; D002784:Cholesterol; D008274:Magnesium