Scalable production of double emulsion drops with thin shells

Area of Science:

• * Microfluidics
• * Colloid and Interface Science
• * Materials Science

Background:

• * Double emulsions are crucial for high-throughput screening and capsule fabrication.
• * Mechanical stability is essential to prevent coalescence during processing and storage.
• * Reducing shell thickness can enhance stability via lubrication effects, but controlled fabrication is challenging.

Purpose of the Study:

• * To develop a microfluidic device for controlled fabrication of double emulsions with thin shells.
• * To achieve high throughput production of double emulsions with reduced shell thickness.
• * To overcome limitations in producing uniform, thin-shelled double emulsions.

Main Methods:

• * Introduction of a novel microfluidic 'aspiration device'.
• * Manipulation of pressure profiles and fluid flow rates within the device.
• * Fabrication of double emulsions with controlled shell thickness.

Main Results:

• * Achieved reduction of double emulsion shell thickness down to 240 nm.
• * Demonstrated a reduction in shell volume by up to 95%.
• * Showed that shell thickness is controllable via pressure profiles and independent of initial shell thickness.

Conclusions:

• * The aspiration device enables high-throughput production of mechanically stable double emulsions.
• * This method allows for the conversion of double emulsions with polydisperse shells into those with uniform, thin shells.
• * The technology facilitates the creation of double emulsions with precisely engineered thin shells for advanced applications.