Acoustofluidic Chromatography for Extracellular Vesicle Enrichment from 4 μL Blood Plasma Samples

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Nanotechnology

Background:

• Extracellular vesicles (EVs) are crucial biomarkers for disease diagnosis.
• Current EV isolation methods often require large sample volumes and are time-consuming.
• High-throughput and sensitive methods for EV enrichment are needed for clinical applications.

Purpose of the Study:

• To develop and characterize a novel acoustofluidic chromatography platform for nanoparticle and EV enrichment.
• To evaluate the platform's performance in terms of trapping efficiency, capacity, and purity of isolated EVs.
• To demonstrate the platform's potential for rapid EV isolation from small blood plasma volumes.

Main Methods:

• Acoustofluidic chromatography platform utilizing a packed bed of polystyrene beads actuated acoustically.
• Characterization using fluorescent polystyrene nanoparticles (25 nm) across a frequency range (0.45-4 MHz).
• EV isolation from blood plasma, followed by protein background analysis using Micro BCA.

Main Results:

• Demonstrated efficient trapping of nanoparticles as small as 25 nm at various frequencies.
• Achieved high recovery rates (up to 42.9%) at low input power (55 mW) and high flow rates (200 μL/min).
• Isolated 2 × 10⁸ EV-sized particles from 4 μL plasma in 8 min with low protein contamination (<2 μg/mL).

Conclusions:

• The developed acoustofluidic chromatography platform offers an efficient, high-throughput method for nanoparticle and EV enrichment.
• Minimal sample volume requirement and rapid processing make it suitable for diagnostic applications.
• Potential for downstream analyses like mass spectrometry and future development for clinical use.