An Integrated Detection Method for Flow Viscosity Measurements in Microdevices

Area of Science:

• Biomedical Engineering
• Microfluidics
• Materials Science

Background:

• Point-of-care devices are crucial for rapid sample analysis.
• Integrating diverse measurement techniques enhances diagnostic capabilities.
• Microtechnology offers miniaturized solutions for complex analyses.

Purpose of the Study:

• To fabricate and validate an integrated microfluidic rheometer for point-of-care viscosity measurements.
• To develop a portable, user-friendly device for analyzing both Newtonian and Non-Newtonian fluids.
• To assess the device's performance with biological samples like blood.

Main Methods:

• Fabrication of a microfluidic chip for flow velocity measurement.
• Integration with a USB-powered data acquisition system and custom software.
• Testing with standard fluids (Mili-Q water, Ethylene-glycol solutions) and human blood samples.
• Calculation of viscosity based on measured average flow velocity.

Main Results:

• Successful fabrication of a hand-held microrheometer.
• Accurate viscosity determination for Newtonian and Non-Newtonian fluids.
• Measurement of non-linear viscosity for 0.08 ml blood samples in under 30 seconds.
• Achieved 93% accuracy across a wide shear rate range.

Conclusions:

• The developed microrheometer is a simple, easy-to-handle, and fabricate device.
• Its portability and speed make it suitable for point-of-care applications.
• The technology's versatility allows integration into various fluidic microsystems, including biomedical applications.