Related Experiment Video
Updated: Nov 30, 2025
Cell-free Biochemical Fluorometric Enzymatic Assay for High-throughput Measurement of Lipid Peroxidation in High Density Lipoprotein
Published on: October 12, 2017
A homogeneous assay to determine high-density lipoprotein subclass cholesterol in serum
Kazumi Matsushima-Nagata1, Hiroyuki Sugiuchi1, Kensaku Anraku1
1Kumamoto Health Science University, Kumamoto, Japan.
Insights
A new assay simplifies measuring high-density lipoprotein cholesterol (HDL-C) subclasses (HDL2-C and HDL3-C). This method offers accurate, convenient, and low-cost routine diagnosis of HDL-C subclasses in serum.
Area of Science:
- Clinical Chemistry
- Biochemistry
- Lipid Metabolism
Background:
- Accurate measurement of high-density lipoprotein cholesterol (HDL-C) subclasses, specifically HDL2-C and HDL3-C, is crucial for cardiovascular risk assessment.
- Existing methods for determining HDL-C subclasses are often complex, labor-intensive, and require specialized expertise, limiting their routine clinical application.
Purpose of the Study:
- To develop a convenient, homogeneous, and accurate assay for quantifying HDL-C subclasses (HDL2-C and HDL3-C) in serum.
- To establish a cost-effective method for routine clinical diagnosis of HDL-C subclasses using standard automated analyzers.
Main Methods:
- Investigated cholesterol reactivities of lipoprotein fractions (HDL2, HDL3, LDL, VLDL) using polyethylene glycol (PEG)-modified enzymes.
- Optimized concentrations of dextran sulfate and magnesium nitrate to achieve selective reaction with HDL3-C.
- Utilized dynamic light scattering to measure particle size changes in lipoprotein fractions.
- Validated the assay against ultracentrifugation in serum samples from healthy volunteers and type 2 diabetes patients.
Main Results:
- Optimized concentrations of dextran sulfate and magnesium nitrate induced selective reactivity for HDL3-C by altering particle sizes of other lipoproteins (HDL2, LDL, VLDL) while maintaining HDL3 particle size.
- The developed assay demonstrated good correlation with ultracentrifugation for determining HDL-C subclasses.
- The assay allows for accurate measurement without the need for sample preprocessing.
Conclusions:
- A novel, convenient, and homogeneous assay for determining HDL-C subclasses (HDL2-C and HDL3-C) has been developed.
- This assay can be readily implemented on general automatic analyzers, enabling low-cost routine diagnosis.
- The method provides a valuable tool for assessing cardiovascular risk through precise HDL-C subclass quantification.
Abstract:
Existing methods to measure high-density lipoprotein cholesterol (HDL-C) subclasses (HDL2-C and HDL3-C) are complex and require proficiency, and thus there is a need for a convenient, homogeneous assay to determine HDL-C subclasses in serum. Here, cholesterol reactivities in lipoprotein fractions [HDL2, HDL3, low-density lipoprotein (LDL), and very-low-density lipoprotein (VLDL)] toward polyethylene glycol (PEG)-modified enzymes were determined in the presence of varying concentrations of dextran sulfate and magnesium nitrate. Particle sizes formed in the lipoprotein fractions were measured by dynamic light scattering. We optimized the concentrations of dextran sulfate and magnesium nitrate before assay with PEG-modified enzymes to provide selectivity for HDL3-C. On addition of dextran sulfate and magnesium nitrate, the sizes of particles of HDL2, LDL, and VLDL increased, but the size of HDL3 fraction particles remained constant, allowing only HDL3-C to participate in coupled reactions with the PEG-modified enzymes. In serum from both healthy volunteers and patients with type 2 diabetes, a good correlation was observed between the proposed assay and ultracentrifugation in the determination of HDL-C subclasses. The assay proposed here enables convenient and accurate determination of HDL-C subclasses in serum on a general automatic analyzer and enables low-cost routine diagnosis without preprocessing.
