Controlled formulation of monodisperse double emulsions in a multiple-phase microfluidic system

Area of Science:

• * Fluid dynamics and microfluidics.
• * Colloid and interface science.
• * Materials science and nanotechnology.

Background:

• * Microfluidic devices offer precise control over droplet generation.
• * Formulating stable double emulsions with specific compositions is challenging.
• * Controlling droplet size and encapsulation is crucial for applications.

Purpose of the Study:

• * To present an overview of recent work on microfluidic device application for double emulsion formulation.
• * To highlight key issues in controlled encapsulation of highly monodisperse drops.
• * To demonstrate the production of various double emulsion types and complex encapsulated structures.

Main Methods:

• * Utilized microfluidic devices with serially connected hydrophobic and hydrophilic microchannels.
• * Manipulated viscous shearing and interfacial tension in low Reynolds number streams for droplet formation.
• * Reversed the order of hydrophobic and hydrophilic junctions to control emulsion type.

Main Results:

• * Achieved regular periodicity in microdroplet formation.
• * Successfully produced water-in-oil-in-water and oil-in-water-in-oil double emulsions.
• * Demonstrated the encapsulation of two distinct aqueous droplets within organic droplets.

Conclusions:

• * Microfluidic devices provide a robust platform for controlled double emulsion synthesis.
• * The presented methods allow for precise control over droplet size and internal structure.
• * This technology opens avenues for advanced materials and drug delivery systems.