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Biocompatible/Biodegradable Electrowetting on Dielectric Microfluidic Chips with Fluorinated CTA/PLGA
Kaidi Zhang1, Lei Chao2, Jia Zhou3
1ASIC and System State Key Lab, School of Microelectronics, Fudan University, Shanghai 200433, China. zhangkaidi186@163.com.
Materials (Basel, Switzerland)
|August 4, 2018
Summary
Researchers developed a super-hydrophobic film using cellulose triacetate and PLGA for biocompatible electrowetting devices. This material reduces droplet adhesion, offering a promising alternative to traditional hydrophobic layers.
Area of Science:
- Materials Science
- Biotechnology
- Surface Chemistry
Background:
- Biocompatibility of dielectric and hydrophobic layers is a key challenge for electrowetting-on-dielectric (EWOD) devices.
- Existing materials like Teflon® or Cytop® may not meet stringent biocompatibility requirements for certain applications.
Purpose of the Study:
- To develop a novel super-hydrophobic film with enhanced biocompatibility for EWOD applications.
- To investigate the surface properties and electrowetting performance of a new composite material.
Main Methods:
- Fabrication of a super-hydrophobic film using reactive ion etching (RIE) of fluorinated cellulose triacetate (CTA) and poly (lactic-co-glycolic acid) (PLGA).
- Characterization using X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM).
- Evaluation of electrowetting properties including contact angle, contact angle hysteresis, and droplet transportation.
Main Results:
- The CTA/PLGA film achieved a water contact angle of approximately 160°, indicating super-hydrophobicity.
- XPS and AFM confirmed the formation of C-F bonds and increased surface roughness contributing to super-hydrophobicity.
- Impregnation with silicon oil significantly reduced contact angle hysteresis and contact line pinning during AC electrowetting.
Conclusions:
- The developed fluorinated CTA/PLGA film demonstrates excellent super-hydrophobic properties and reduced droplet adhesion.
- This material offers a promising biocompatible alternative to conventional hydrophobic layers in EWOD devices.
- The findings pave the way for advanced biocompatible microfluidic and lab-on-a-chip systems.
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