Measurement of single low-density lipoprotein particles by atomic force microscopy
Toshihiro Sakurai1, Seiji Takeda, Jun-ya Takahashi
1Faculty of Health Sciences, Hokkaido University, Sapporo, Japan.
Annals of Clinical Biochemistry
|August 1, 2013
Summary
Atomic force microscopy (AFM) can distinguish between large low-density lipoprotein (LDL) and small dense LDL (sd-LDL) particles. This technique may aid in assessing coronary artery disease (CAD) risk by analyzing lipoprotein size.
Area of Science:
- Biophysics
- Cardiovascular Science
- Nanotechnology
Background:
- Lipoprotein particle size is a known risk factor for coronary artery disease (CAD).
- Differentiating between LDL subpopulations, such as large LDL and small dense LDL (sd-LDL), is crucial for accurate risk assessment.
Purpose of the Study:
- To evaluate the feasibility of using atomic force microscopy (AFM) for measuring the size of large LDL and sd-LDL particles.
- To compare AFM measurements with traditional electron microscopy (EM) for lipoprotein sizing.
Main Methods:
- Lipoprotein fractions (large LDL and sd-LDL) were isolated using ultracentrifugation.
- Particle sizes were measured using atomic force microscopy (AFM) in tapping mode.
- AFM measurements were compared against those obtained from electron microscopy (EM).
Main Results:
- AFM successfully differentiated between large LDL (20.6 ± 1.9 nm) and sd-LDL (16.2 ± 1.4 nm) from healthy volunteers (P < 0.05).
- Electron microscopy also showed significant size differences (large LDL: 23.2 ± 1.4 nm; sd-LDL: 20.4 ± 1.4 nm; P < 0.05).
- Statistically significant differences were observed between AFM and EM measurements for both large LDL and sd-LDL particle sizes (P < 0.05).
Conclusions:
- Atomic force microscopy (AFM) is capable of distinguishing between small dense LDL (sd-LDL) and large LDL particles based on size.
- AFM shows potential as a valuable tool for evaluating coronary artery disease (CAD) risk through lipoprotein size analysis.
