A hybrid paper and microfluidic chip with electrowetting valves and colorimetric detection

Area of Science:

• Biomedical Engineering
• Microfluidics
• Diagnostics

Background:

• Sequential fluid delivery is crucial for point-of-care diagnostics.
• Minimizing external equipment is a key challenge in microfluidic device development.

Purpose of the Study:

• To develop an automated microfluidic chip with integrated electrowetting valves for sequential reagent delivery.
• To demonstrate a miniaturized, capillary-driven system for point-of-care diagnostics.

Main Methods:

• Fabrication of a disposable polymeric microfluidic device using laser ablation and inkjet printing.
• Integration of electrowetting valves and a porous membrane with capture molecules and colloidal gold labels.
• Utilizing a low voltage supply for sequential valve operation and reagent delivery.

Main Results:

• Demonstrated sequential delivery of sample and rinsing reagents using on-chip electrowetting valves.
• Successfully executed an automated assay for T7 bacteriophage detection.
• The microfluidic chip operated without external pumping equipment.

Conclusions:

• The developed microfluidic chip with electrowetting valves offers a promising platform for automated, point-of-care diagnostic assays.
• The capillary-driven, disposable device simplifies complex fluid handling for diagnostics.
• This technology minimizes external equipment requirements for efficient diagnostic procedures.