Dielectrophoretic Separation of Particles Using Microfluidic Chip with Composite Three-Dimensional Electrode

Area of Science:

• Materials Science
• Microfluidics
• Biotechnology

Background:

• Integrating 3D microelectrodes onto polydimethylsiloxane (PDMS) microfluidic chips presents significant fabrication challenges.
• Existing methods often struggle with robust electrode integration and precise control within microfluidic systems.

Purpose of the Study:

• To develop and characterize a novel composite 3D microelectrode for enhanced integration with PDMS microfluidic chips.
• To investigate the efficacy of these composite 3D microelectrodes in particle separation using dielectrophoresis.
• To demonstrate non-destructive, efficient, and accurate separation of microparticles based on size.

Main Methods:

• Fabrication of a composite 3D electrode using silver (Ag) powder and PDMS, with ethyl acetate as a dispersant.
• Development of a micromachining technique for precise shaping and bonding of 3D microelectrodes to PDMS chips.
• Utilizing theoretical calculations, numerical simulations, and experimental verification to study dielectrophoresis.

Main Results:

• Successfully fabricated and integrated composite 3D microelectrodes onto PDMS microfluidic chips.
• Demonstrated the capability of the device to separate polystyrene particles of 20-, 10-, and 5-μm sizes.
• Achieved non-destructive, efficient, and accurate particle separation through dielectrophoresis.

Conclusions:

• The developed composite 3D microelectrode offers a viable solution for integrating electrodes into PDMS microfluidic devices.
• This technology enables precise and efficient size-based particle separation via dielectrophoresis.
• The findings have implications for advanced microfluidic applications in particle manipulation and analysis.