Numerical and Experimental Investigation on Water-Me 2 SO Mixing in Microfluidic Device for Oocyte Cryopreservation.

BACKGROUND: Oocyte vitrification is a practical tool in assisted reproductive technology and fertility preservation. However, vitrification requires high concentration of cryoprotectants (CPAs), which may cause osmotic injury and is toxic to oocytes during the addition and removal process of CPAs. OBJECTIVE: To minimize osmotic and toxic injuries, a microfluidic device was designed to provide continuous concentration changes of CPAs to oocytes. METHODS: Numerical simulations were first used to investigate the effects of geometric parameters of microchannel on water-Me2SO mixing performance. A microfluidic device was then fabricated via soft lithography. Distilled water and 30% Me2SO containing 1mM fluorescence dye FITC were mixed using the microfluidic device to verify the CPA diffusion behavior. RESULTS: The mixing performance in the microfluidic device strongly depends on the channel geometry and the flow rates of the fluids. Linear CPA loading profiles with diverse slopes were obtained by controlling the flow rate and the loading time of CPA and the buffer solution in the microfluidic device. CONCUSION: The designed microfluidic device can yield linear CPA loading profiles with different slopes.