Charge-controlled microfluidic formation of lipid-based single- and multicompartment systems

Area of Science:

• Biotechnology
• Materials Science
• Synthetic Biology

Background:

• Giant unilamellar vesicles (GUVs) are crucial for modeling cell membranes and functions.
• Current methods for GUV production are often low-throughput and lack control over vesicle formation.
• Synthetic cell model systems require adaptable compartments for bottom-up construction.

Purpose of the Study:

• To introduce a high-throughput, on-demand method for creating giant unilamellar vesicles (GUVs) and multicompartment synthetic cell models.
• To demonstrate control over vesicle formation by tuning interfacial properties.
• To provide a method for releasing functional GUVs into physiological buffers.

Main Methods:

• Utilized microfluidics to encapsulate small unilamellar vesicles within block-copolymer surfactant-stabilized water-in-oil droplets.
• Controlled interfacial charge density by varying molar ratios of uncharged and charged fluorosurfactants (Krytox).
• Analyzed the transition from multicompartment systems to GUVs using confocal fluorescence microscopy, cryo-scanning electron microscopy, and interfacial tension measurements.

Main Results:

• Successfully generated GUVs and multicompartment systems by tuning droplet interface charge.
• Demonstrated a method for releasing GUVs from the oil phase into aqueous buffer with high yield.
• Showcased the ability to transition from multicompartment systems to 3D-supported lipid bilayers.

Conclusions:

• This microfluidics-based approach offers a versatile and high-throughput platform for GUV and synthetic cell model production.
• The tunable interfacial properties provide precise control over compartment formation.
• The technology expands the utility of GUVs in bottom-up synthetic biology and related fields.