Biofunctionalization of electrowetting-on-dielectric digital microfluidic chips for miniaturized cell-based...

Area of Science:

• Microfluidics
• Biotechnology
• Surface Science

Background:

• Electrowetting-on-dielectric (EWOD) devices are crucial for digital microfluidic applications.
• Controlled biofunctionalization of hydrophobic surfaces is essential for cell-based assays.
• Existing methods often compromise surface properties or biocompatibility.

Purpose of the Study:

• To develop a controlled biofunctionalization technique for EWOD microfluidic chips.
• To enable precise spatial patterning of biomolecules on hydrophobic chip surfaces.
• To facilitate adherent cell-based assays and heterogeneous bio-assays.

Main Methods:

• Utilized a dry lift-off method employing a removable Parylene-C mask.
• Achieved spatially controlled micropatches of biomolecules on the Teflon-AF® layer.
• Maintained chip surface hydrophobicity and biocompatibility throughout the process.

Main Results:

• Demonstrated precise control over micropatch geometry and dimensions for cell arraying.
• Enabled patterning of cells as clusters or single cells on the microfluidic chip.
• Validated the biocompatibility and effectiveness of the biofunctionalization technique.

Conclusions:

• The dry Parylene-C lift-off technique offers precise biofunctionalization for digital microfluidic chips.
• This method enhances the utility of EWOD devices for complex cell-based assays.
• The technique holds significant potential for diverse biomedical applications requiring controlled cell patterning.