Inkjet-printed electronics for rapid and low-cost prototyping of digital microfluidic devices using an off-the-shelf...

Area of Science:

• Microfluidics
• Lab-on-a-chip technology
• Point-of-care diagnostics

Background:

• Digital microfluidics (DMF) is advancing lab-on-a-chip technology for point-of-care diagnostics.
• Rapid and affordable prototyping is essential for translating DMF devices into real-world applications.
• Current fabrication methods often require expensive equipment and specialized facilities.

Purpose of the Study:

• To present a rapid, low-cost method for prototyping digital microfluidic devices.
• To demonstrate the feasibility of using an unmodified desktop inkjet printer for DMF chip fabrication.
• To lower the barriers to entry for researchers in the DMF field.

Main Methods:

• Characterization of an inkjet printer for depositing Ag-ink tracks on PET and glass substrates.
• Fabrication of functional DMF chips using common materials like tape, parafilm, and SU8.
• Assembly of actuation and control circuitry using standard electronic modules.
• Demonstration of a DMF micromixer fabricated with the developed method.

Main Results:

• Achieved maximum surface conductance of 7.69 Ω-1/cm2 using inkjet-printed Ag-ink.
• Enabled actuation voltages as low as 144 VDC and 92 VAC@100 kHz for whole-blood droplets.
• Successfully fabricated and tested a DMF micromixer, confirming its mixing performance via image processing.

Conclusions:

• Inkjet printing offers a cost-effective and accessible alternative to traditional microfabrication for DMF devices.
• This approach significantly reduces the cost and complexity of prototyping DMF systems.
• The developed method facilitates accessible research and development in DMF-based point-of-care diagnostics.