Microfluidic on-chip valve and pump for applications in immunoassays

Area of Science:

• Biomedical Engineering
• Microfluidics
• Biosensing

Background:

• Existing on-chip valves often require complex manufacturing and bulky support systems.
• Simplifying microfluidic systems enhances their practicality and accessibility.

Purpose of the Study:

• To present a straightforward, serially connectable on-chip valve.
• To develop a compact on-chip pump for microfluidic applications.
• To demonstrate the utility of the system in point-of-care immunoassays.

Main Methods:

• Designed on-chip valves utilizing flexure strips and linear actuators for one-way liquid flow.
• Integrated valves to form a compact on-chip pump system (0.65 dm³, 0.56 kg).
• Performed folic acid immunoassays on clinical samples and simultaneous detection of multiple biomarkers.

Main Results:

• The on-chip valve and pump system demonstrated reliable operation for liquid handling.
• Folic acid immunoassays showed satisfactory reproducibility and acceptable coefficients of variation.
• Simultaneous detection of transferrin, cobalamin, and folic acid was achieved on a single chip.

Conclusions:

• The developed on-chip valve and pump offer a simplified, miniaturized solution for microfluidic systems.
• The system's portability makes it suitable for point-of-care testing applications.
• This technology holds promise for various immunoassays and other biosensing applications.