[Lipoprotein Analysis -Measurement of Lipoprotein Fractions and Anion-Exchange High-Performance Liquid Chromatography].

Many clinical studies, including Framingham Heart study, have demonstrated that increased LDL choles- terol and decreased HDL cholesterol are associated with the risk of coronary heart disease (CHD), and lipo- protein evaluation is of importance in the prevention and treatment of CHD risk. Lipoprotein analysis methods by high performance liquid chromatography (HPLC) are divided broadly into 2 categories (HPLC with gel-filtration column and with anion-exchange column), and both methods can determine lipid levels of fractionated serum lipoproteins in a small volume of around 10 pL within 30 min. In contrast, with the gel- filtration HPLC method by Gaussian approximation following the particle sizes, the anion-exchange HPLC method elutes lipoproteins following the ion intensity of the lipoprotein particle surface and the hydrophobic property, and determines cholesterol levels of separated lipoproteins without overlapping lipoprotein frac- tions. We have established a method with anion-exchange chromatography using a 1.0-mL injection volume that 5.2 min takes to assay one sample. The within-day and between-day assay coefficients of variation of lipoprotein cholesterol values were 0.33-4.31 and 2.37-9.19%, respectively. Previous studies generating fractionated lipoprotein cholesterol data using anion-exchange HPLC revealed the clinical significance in a variety of settings and, in Japan, this rapid anion-exchange HPLC assay was approved as a medical examina- tion covered by health insurance for medical service fees in 2013, and the anion-exchange HPLC method for lipoprotein fraction cholesterol measurement has the potential to offer further clinical benefit. [Review].