Thermo-acoustofluidic separation of vesicles based on cholesterol content

Area of Science:

• Biophysics
• Cell Biology
• Biotechnology

Background:

• Cellular stiffness is a key biomarker for diseases, influenced by cholesterol content.
• Acoustophoresis separates cells by density and compressibility, but struggles with similar vesicle properties.
• Thermo-acoustophoresis introduces a temperature dimension to overcome separation limitations.

Purpose of the Study:

• To evaluate the acoustic contrast temperature of vesicles with varying cholesterol molar ratios (X_chol).
• To develop a multi-stage lab-on-a-chip method for separating mixtures of vesicles.
• To demonstrate the efficacy of thermo-acoustophoresis for vesicle separation and diagnostics.

Main Methods:

• Utilized thermally-assisted acoustophoresis (thermo-acoustophoresis) to manipulate vesicles.
• Investigated vesicles with distinct cholesterol molar ratios (X_chol = 0.1, 0.2, 0.3).
• Developed and implemented a multi-stage lab-on-a-chip device for vesicle separation.

Main Results:

• Achieved separation efficiencies exceeding 93% for a three-vesicle mixture.
• Demonstrated the ability to differentiate vesicles based on cholesterol-induced changes in acoustic properties.
• Quantified the acoustic contrast temperature (T_Φ) at different cholesterol concentrations.

Conclusions:

• Thermo-acoustophoresis enables efficient, label-free separation of vesicles based on cholesterol content.
• This method holds significant promise for the diagnosis and separation of cells and extracellular vesicles.
• The developed lab-on-a-chip approach offers a rapid and simple solution for complex biological sample analysis.