Charge density profiling of circulating human low‐density lipoprotein particles by capillary zone electrophoresis

Abstract

Capillary zone electrophoresis (CZE) has been utilized to profile the low-density (LDL) particles in human blood serum in this study. A 5 mM sodium phosphate buffer, pH 7.40, was chosen as the most suitable CE buffer and an extensive ultrafiltration (UF) procedure was applied to purify the LDL sample. Two LDL particle species, LDL with lower mobility and LDL- with higher mobility were observed. The electropherograms were highly reproducible with good precision of effective mobilities, corrected peak areas (CPAs) and CPA ratio of LDL-/LDL. LDL particles shown on the electropherogram were also characterized by several procedures. The applications of Sigma HDL cholesterol reagent and CE on-line 2-propanol precipitation indicated that the two particle species shown in the electropherogram belong to LDL. The LDL particles were found to associate with the buoyant LDL fraction and the LDL- particles associate with the dense LDL fraction. This study utilizes CZE for the profiling of LDL isoforms and provides a new analytical method for the resolution of LDL subspecies. It demonstrates a high-mobility LDL particle which circulates in healthy subjects and diminishes in atherosclerotic patients. Diminution of the high-mobility LDL subspecies may be linked to minimal formation of arterial plaque in atherosclerotic patients.

Microchip‐based small, dense low‐density lipoproteins assay for coronary heart disease risk assessment

“…Eventually, lipoprotein fractions migrate with the EOF on the basis of their different particle charge density of mass. Liu et al [22] had demonstrated two LDL particles with significantly different charge/volume ratios based on their electrophoretic mobilities. Ceriotti et al [14] suggested that the microchip-based CE could be suited to distinguishing between different LDL types for certain diagnostic applications.…”

In vitro oxidized and glycated human low-density lipoprotein particles characterized by capillary zone electrophoresis

“…In addition, it was also observed that without ultrafiltration to clean the anticoagulants in LDL samples, the oxidation and glycation reactions were not successful. The optimal CE buffer chosen was 5 mM PB, pH 7.4, which was similar to that chosen in our previous study [18]. However, the mobilities and CE profiles observed in this study for native LDL particles are not exactly the same as that observed in the previous study.…”

“…Recently, Liu difference of LDL isoforms and peak effective mobilities [18]. Liu et al has also used CZE to separate and determine in vitro oxidized phosphatidylcholine (PC) since PC is the most important phospholipids on LDL particles [19].…”

“…The objective of this study was to determine in vitro oxidized and glycated LDL particles by a simple CZE method which was a modification of our previous study [18]. In vitro oxidized and glycated LDL particles were used to monitor the in vivo modification of LDL particles in patients.…”

Microchip-based human serum atherogenic lipoprotein profile analysis

“…Liu and coworkers demonstrated that capillary electrophoresis (CE) can be used to separate two LDL particles with significantly different charge/volume ratios given that the different ratios result in different electrophoretic mobilities [11]. Schmitz and coworkers developed a capillary isotachophoresis procedure for the separation of lipoproteins into 14 subclasses [12].…”