Serum high-density and low-density lipoprotein cholesterol determined by ultracentrifugation and high-performance liquid chromatography

Objective To investigate the measurement of serum high-density lipoprotein (HDL) cholesterol (HDLC) and low-density lipoprotein (LDL) cholesterol (LDLC) by ultracentrifugation and high-performance liquid chromatography ( HPLC) and to develop a reliable method for HDLC and LDLC measurements for use as a reference method. Methods Serum aliquots were centrifuged in the presence of 2-mercaptoethanol and proline at a density of 1. 063 g/ml for the separation of HDL and in the presence of proline at a density of 1. 006 g/ml for the separation of HDL and LDL Cholesterol concentrations of the lipoprotein fractions were analyzed by HPLC. Results 2-mercaptoethanol and proline together effectively eliminated the contamination of lipoprotein (a) in HDL separated by ultracentrifugation that enabled reliable separation of lipoproteins by ultracentrifugation and precise measurement of HDLC and LDLC. The total CVs for HDLC and LDLC were 0. 96% -2. 07% and 0. 65% -1.12% , respectively. Conclusions A new method for the measurement of HDLC and LDLC by ultracentrifugation and HPLC has been established It is reliable, precise and simple and may be used as a candidate reference method for HDLC and LDLC measurements.