title: A novel and precise method for simultaneous measurement of serum HDL and LDL subfractions and lipoprotein (a) cholesterol by ultracentrifugation and high-performance liquid chromatography.
abstract: BACKGROUND
  We developed an ultracentrifugation and high-performance liquid chromatography (HPLC) method for simultaneous measurement of cholesterol in serum high density lipoprotein (HDL) and low density lipoprotein (LDL) subfractions and lipoprotein (a) [Lp(a)].
  
  
  METHODS
  Serum aliquots of 0.05 ml were centrifuged at background densities of 1.006, 1.044 kg/l, and in the presence of β-mercaptoethanol (ME) at background densities of 1.044, 1.063 and 1.125 kg/l for the separation of lipoprotein subfractions and Lp(a). Cholesterol levels in the ultracentrifugal bottom fractions were analyzed by HPLC.
  
  
  RESULTS
  ME effectively dissociated Lp(a) into apolipoprotein (a) and Lp(a) remnant [Lp(a-)]. Lp(a-) showed a distinctive density distribution from that of the native Lp(a). Based on these data, a method was developed to separate lipoprotein into subfractions and Lp(a) by ultracentrifugation. The separated HDL and LDL subfractions were not contaminated with Lp(a). This method is highly precise with the total CVs for the measurement of HDL2-C, HDL3-C, LDLa-C, LDLb-C and Lp(a)-C 0.85%-2.66%, 0.87%-3.21%, 0.86%-1.11%, 2.59%-6.35% and 4.42%-12.29%, respectively.
  
  
  CONCLUSIONS
  A new method for the separation of HDL and LDL subfractions and Lp(a) and simultaneous measurement of cholesterol by ultracentrifugation and HPLC have been established. It is precise and sensitive and can be used in research or clinical laboratories for lipoprotein profiling.
authors.affiliation: The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, Beijing, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Dong
authors.forename: Hanbang
authors.initials: H
authors.lastname: Guo
authors.forename: Ruiyue
authors.initials: R
authors.lastname: Yang
authors.forename: Hongxia
authors.initials: H
authors.lastname: Li
authors.forename: Shu
authors.initials: S
authors.lastname: Wang
authors.forename: Jiangtao
authors.initials: J
authors.lastname: Zhang
authors.forename: Weiyan
authors.initials: W
authors.lastname: Zhou
authors.forename: Wenxiang
authors.initials: W
authors.lastname: Chen
mesh_terms: D000328:Adult; D008076:Cholesterol, HDL / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005260:Female; D006801:Humans; D017270:Lipoprotein(a) / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D014461:Ultracentrifugation / Q000379:methods*
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D017270:Lipoprotein(a)