Flexible Microfluidic Devices for Tunable Formation of Double Emulsion

Area of Science:

• Droplet-based microfluidics
• Materials science
• Chemical engineering

Background:

• Double emulsions are advanced dispersion systems superior to single emulsions for encapsulating sensitive liquids.
• Their applications span biology, food technology, cosmetics, and environmental sciences.
• Microfluidic emulsification enables precise production of monodisperse double emulsions, but controlling size and thickness is challenging.

Purpose of the Study:

• To develop a facile method for generating monodisperse double-emulsion droplets with tunable core size and shell thickness.
• To overcome the limitations of flow rate control in microfluidic emulsification.
• To demonstrate a flexible and stretchable microfluidic device for precise control over droplet generation.

Main Methods:

• Development of a proof-of-concept flexible and stretchable microfluidic device.
• Utilizing device stretching to adjust channel dimensions and control droplet generation.
• Investigating three stretching cases to assess control over core size, shell thickness, and generation frequency.

Main Results:

• Stretching the microfluidic device successfully tuned core size and shell thickness.
• Device strain led to increased core and shell volumes (up to ~84% and ~23%, respectively).
• Stretching decreased the double emulsion droplet generation frequency.

Conclusions:

• A novel method using a stretchable microfluidic device enables tunable generation of double emulsions.
• This approach offers precise, on-site control over droplet characteristics without altering fluid flow rates.
• The technology advances droplet-based microfluidics for applications requiring high precision and reproducibility.