Selection of healthy sperm based on positive rheotaxis using a microfluidic device

Area of Science:

• Biomedical Engineering
• Reproductive Biology
• Microfluidics

Background:

• Sperm motility and morphology are crucial for natural conception.
• Efficient sperm selection methods are needed for assisted reproductive technologies.
• Rheotaxis, or movement in response to fluid flow, is a natural sperm guidance mechanism.

Purpose of the Study:

• To develop a microfluidic chip that isolates healthy, functional sperm cells from semen samples.
• To leverage the natural rheotaxis behavior of sperm for efficient sperm sorting.
• To provide a low-cost, easy-to-operate solution for clinical sperm selection.

Main Methods:

• A microfluidic chip with interconnected chambers and microchannels was designed.
• Semen samples were processed using controlled fluid flow to induce positive rheotaxis.
• Sperm cells were directed towards a collection chamber based on their motile and functional characteristics.

Main Results:

• The microfluidic chip achieved nearly 100% sperm motility.
• A significantly higher percentage of morphologically normal sperm cells were isolated.
• Reduced sperm DNA fragmentation was observed in the sorted sperm compared to controls.
• The chip demonstrated effectiveness at a flow rate of 0.5 μL min^-1.

Conclusions:

• The developed microfluidic chip effectively isolates high-quality sperm cells by utilizing positive rheotaxis.
• This technology offers a promising, cost-effective, and user-friendly method for sperm sorting in clinical settings.
• The chip enhances sperm parameters crucial for successful conception, addressing a key need in fertility treatments.