Affordable method for channel geometry-specific flow control in microfluidics without commercial pumps.

Area of Science:

• Microfluidics
• Fluid Dynamics
• Biotechnology

Background:

• Precise flow control is essential for microfluidic experiments.
• Commercial pumps and pressure regulators are expensive and limit accessibility.
• Existing methods lack cost-effective solutions for reliable flow control.

Purpose of the Study:

• To develop a calibration-based strategy for stable microfluidic flow control using inexpensive equipment.
• To establish predictable relationships between channel geometry, pressure drop (Δp), and flow rate (Q).
• To enable microfluidic systems to operate reliably without specialized commercial pumps.

Main Methods:

• Fabrication of silicon-glass microfluidic chips with varied channel dimensions (width, depth, length).
• Experimental testing to quantify the effect of channel geometry on hydrodynamic resistance.
• Development of a calibration framework linking geometry to pressure drop and flow rate.

Main Results:

• Consistent, geometry-dependent scaling of pressure drop (Δp) and flow rate (Q) was observed.
• Experimental results closely matched theoretical predictions for hydrodynamic resistance.
• A calibration framework was established for pre-determining safe operating conditions.

Conclusions:

• A cost-effective calibration strategy enables reliable syringe-driven flow control in microfluidics.
• Chip geometry is a critical design parameter for achieving predictable flow regimes.
• This method enhances accessibility to microfluidic research by reducing equipment costs.