A novel microfluidic system to separate sperm using spermatozoa inherent motion and inertial effect

Area of Science:

• Reproductive Biology
• Biomedical Engineering
• Microfluidics

Background:

• Conventional sperm separation for in vitro fertilization (IVF) relies on centrifugation.
• Centrifugation may cause DNA damage to sperm, potentially impacting IVF outcomes.
• There is a need for non-invasive sperm separation techniques.

Purpose of the Study:

• To design and evaluate a novel microchip for passive, non-invasive sperm separation.
• To separate progressively motile spermatozoa for use in IVF.
• To avoid potential sperm DNA damage associated with centrifugation.

Main Methods:

• A two-stage microchip device was designed for sperm separation.
• The first stage utilizes lateral differentiation and rapid divergence to separate sperm from round cells.
• The second stage isolates high-quality sperm based on their natural motility.

Main Results:

• Preliminary tests were conducted using standard particles.
• The microchip demonstrated effective separation of sperm and round cells.
• At an optimized flow rate of 1.7 ml/h, a significant increase in progressively motile spermatozoa concentration was observed at the outlet compared to the initial sample.

Conclusions:

• The novel microchip provides an effective, non-invasive method for separating progressively motile spermatozoa.
• This passive separation technique offers a promising alternative to centrifugation in IVF procedures.
• The microchip design has the potential to improve sperm quality for assisted reproductive technologies.