Molecular diffusion analysis of dynamic blood flow and plasma separation driven by self-powered microfluidic devices

Area of Science:

• Microfluidics
• Biomedical Engineering
• Fluid Dynamics

Background:

• Microfluidic devices offer efficient on-chip blood testing.
• Self-powered fluid flow is crucial for portable diagnostics.
• Understanding fluid dynamics in polydimethylsiloxane (PDMS) microfluidics is limited.

Purpose of the Study:

• To develop a predictive model for fluid dynamics in self-powered microfluidic devices.
• To enable precise control over fluid flow rates.
• To demonstrate direct plasma separation from whole blood on-chip.

Main Methods:

• Proposed a pressure-driven diffusion model incorporating Fick's law and the ideal gas law.
• Utilized vacuum pocket-assisted, self-powered microfluidic devices for experimental validation.
• Linked self-powered fluid flow to sedimentation for plasma separation.

Main Results:

• Model results closely matched experimental fluid dynamics.
• Precisely tuned flow rates by adjusting vacuum pocket geometry.
• Achieved direct plasma separation from whole blood without external power sources.

Conclusions:

• The proposed model accurately describes fluid dynamics in self-powered microfluidic devices.
• Vacuum pocket geometry is a key parameter for flow rate control.
• Self-powered microfluidics can facilitate simple, efficient blood component separation for diagnostics.