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Double Emulsion Generation Using a Polydimethylsiloxane PDMS Co-axial Flow Focus Device
Published on: December 25, 2015
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Rapid Patterning of PDMS Microfluidic Device Wettability Using Syringe-Vacuum-Induced Segmented Flow in Nonplanar
Chang-Hyung Choi1,2, Hyomin Lee1,3, David A Weitz1
1John A. Paulson School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States.
ACS Applied Materials & Interfaces
|January 17, 2018
Summary
We developed a rapid method using layer-by-layer (LbL) deposition to pattern PDMS microfluidic device surfaces. This technique enables precise control over wetting properties for producing monodisperse double and triple emulsions.
Area of Science:
- Materials Science
- Chemical Engineering
- Microfluidics
Background:
- Microfluidic devices are crucial for precise fluid control.
- Controlling surface wetting properties is essential for droplet generation.
- Existing methods for surface patterning can be complex and time-consuming.
Purpose of the Study:
- To present a simple and rapid method for spatially patterning surface wetting properties of PDMS microfluidic devices.
- To enable selective surface modification in complex microfluidic geometries.
- To facilitate the production of monodisperse double and triple emulsions.
Main Methods:
- Utilized layer-by-layer (LbL) deposition of polyelectrolytes.
- Employed syringe-vacuum-induced segmented flow.
- Applied the technique in nonplanar geometry within microfluidic chips.
- Focused on microfluidic chips with multiple flow-focusing junctions.
Main Results:
- Achieved spatial patterning of surface wetting properties on PDMS.
- Demonstrated selective surface modification in microfluidic chips.
- Successfully produced monodisperse double and triple emulsion drops.
- The method proved to be simple and rapid.
Conclusions:
- The LbL deposition technique offers an effective way to control surface wetting in microfluidics.
- This method is suitable for fabricating microfluidic devices for complex emulsion production.
- The developed technique provides a valuable tool for microfluidic applications requiring precise surface patterning.
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