A microfluidic hanging droplet as a programmable platform for mammalian egg vitrification

Area of Science:

• Reproductive Medicine
• Biotechnology
• Microfluidics

Background:

• Oocyte vitrification is crucial for fertility preservation but relies on manual, time-sensitive procedures.
• Current manual methods require high precision in liquid handling and egg manipulation for cryoprotectant exchange.

Purpose of the Study:

• To develop and evaluate a microfluidic platform for automated, programmable oocyte vitrification.
• To improve the precision and efficiency of cryoprotectant exchange and egg handling during vitrification.

Main Methods:

• A microfluidic platform utilizing a millimeter-sized hanging droplet for programmable liquid exchange of cryoprotectants.
• Automated egg extraction and immersion into liquid nitrogen for vitrification.
• Real-time microscopy for monitoring egg morphology during the process.

Main Results:

• The microfluidic platform demonstrated comparable post-vitrification survivability (∼95%) to manual methods in mouse oocytes.
• The platform enables precise, rapid liquid exchange and controlled egg handling.
• Integrated real-time microscopy allows for morphological assessment linked to functional outcomes.

Conclusions:

• The developed microfluidic platform offers a viable automated alternative for oocyte vitrification.
• This technology enhances the automation of embryology, with potential clinical and research applications in reproductive medicine.
• Programmable vitrification via microfluidics can improve consistency and enable further research into oocyte quality.