Problems with PEG-based precipitation methods in the determination of HDL₂- and HDL₃-cholesterol

Abstract

In this study a comparison of two polyethylene glycol (PEG)-based precipitation methods, that is, one using PEG-6000/DS-15000 and the other using two different concentrations of PEG-20000 are presented. The total HDL-cholesterol values measured with the PEG-6000 procedure were higher (13%) than those measured with PEG-20000 (r=0.91) in 16 pooled serum samples tested. The HDL₂- and HDL₃-cholesterol values measured with the two methods differed markedly from each other in spite of the moderate correlation (HDL₂: r=0.74; HDL₃: r=0.26) observed. The advantage of the PEG-20000 method as compared with the other method was its simplicity and rapidity. The separation of HDL₂/HDL₃ is more or less arbitrary in both methods used and further studies are needed for the estimation of optimal conditions for subclass separation.

Key words:

• dextran sulphate 15000
• HDL-cholesterol
• HDL₂-cholesterol
• HDL-subfractions
• lipoprotein analyses
• lipoprotein precipitation
• lipoprotein quantitation
• lipoproteins
• lipoprotein subfraction
• polyethylene glycol 6000/20000