Control of sequential fluid delivery in a fully autonomous capillary microfluidic device.

Area of Science:

• Microfluidics and Biosensor Technology
• Point-of-Care Diagnostics
• Analytical Chemistry

Background:

• Microfluidics and miniaturized biosensors are crucial for developing portable point-of-care (PoC) diagnostic tools.
• These technologies offer reduced reagent consumption and analysis times but face challenges in practical fluid control.
• Interfacing microfluidic devices with reliable fluid control systems remains a significant hurdle for widespread implementation.

Purpose of the Study:

• To demonstrate an innovative capillary microfluidic design for autonomous, sequential liquid handling.
• To present a generalizable system applicable to various microfluidic applications, including diagnostics.
• To overcome the limitations of complex fluid control systems in microfluidic devices.

Main Methods:

• Development of an integrated capillary microfluidic system utilizing capillary pumps for autonomous fluid flow.
• Design allows for sequential insertion of controlled liquid volumes without external valves or active pumping.
• Demonstration of the system's functionality using a model immunoassay protocol.

Main Results:

• Successful autonomous and sequential delivery of different solutions within the microfluidic channel.
• The system operates reliably by simply placing liquids at the designated inlets.
• The capillary microfluidic design proved effective in a model immunoassay, showcasing its practical applicability.

Conclusions:

• The developed capillary microfluidic system offers a simplified and autonomous approach to fluid control.
• This valve-free design enhances the portability and practicality of microfluidic diagnostic devices.
• The technology holds significant potential for advancing point-of-care diagnostics and other microfluidic applications.