Stable, biocompatible lipid vesicle generation by solvent extraction-based droplet microfluidics

Area of Science:

• Biotechnology
• Materials Science
• Chemical Engineering

Background:

• Lipid vesicles are crucial for encapsulating biological entities.
• Controlling vesicle size and stability is essential for applications like artificial cells.
• Existing methods for vesicle generation can be limited by solvent use or size polydispersity.

Purpose of the Study:

• To develop a microfluidic platform for continuous, stable, and monodisperse lipid vesicle generation.
• To enable the encapsulation and manipulation of diverse biological entities.
• To demonstrate the potential for creating artificial cells through in vitro synthesis within these vesicles.

Main Methods:

• Utilized a microfluidic flow-focusing droplet generation design.
• Controlled vesicle size by adjusting fluid flow rates.
• Formed lipid membranes via a controlled solvent extraction process after producing double emulsions.

Main Results:

• Successfully generated stable, monodisperse lipid vesicles with diameters ranging from 20-110 μm.
• Achieved narrow size distribution through precise control of flow rates.
• Demonstrated the stability of generated vesicles with a shelf life of at least 3 months.
• Showcased cell-free in vitro protein synthesis within the lipid vesicles.

Conclusions:

• The developed microfluidic platform offers a robust method for producing high-quality lipid vesicles.
• The platform's solvent-free approach allows for safe encapsulation of sensitive biological materials.
• This work represents a significant step towards the development of functional artificial cells.