Utilization of Motility-Driven Sperm Sorting Microfluidic Chip with Low Cell Damage to Enhance Viability and Apply on Oligozoospermia patients

• Main Authors: Lu, Cheng-Ying, 呂承穎
• Other Authors: Yao, Da-Jeng
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/ngx5pr

碩士 === 國立清華大學 === 動力機械工程學系 === 106 === About the decreasing birth rate of the people in recent years, except for the decline of the desires to have children, many couples are infertile due to stress or other factors. However, with the development of science and technology, there are more than one assisted reproductive technologies (ART) bring benefits to these couples, such as in vitro fertilization (IVF), or more precise IntraCytoplasmic Sperm Injection (ICSI). The above techniques require high-quality and high-motility sperms for pregnancy, and even growing to a healthier fetus. The purpose of this study is to use PDMS microfluidic chips to separate poor sperms by laminar flow and collect high quality sperms by motility to provide to the artificial fertilization process. In this study, micro-scale laminar flow control system is used for live sperms separation of the stock sample, fixed-viscosity sperm sorting experiments and diluted oligozoospermia concentration sorting. This research includes structural design, pump settings, flow cytometry analysis and the analysis of the results. From the results of the stock sample sorting, the viability was obviously improved by the modified flow rate, and the separation with respect to 8: 1 has been greatly improved. Confirming that by appropriate adjustment of the flow rate, the chip is still able to acquire live sperms. In order to improve the low sorting efficiency of stock sample sorting, the semen was fixedly diluted to 2mPa×s viscosity, and sorted by the flow rate 8: 1 (buffer: semen). This chip can enhance the viability for more than 10% on both normal and oligozoospermia samples. In the experiment of diluted oligozoospermia sample sorting, the average viability can be increased at least 10% after separation by this chip for any concentrations, and the sorting efficiency is higher than 10% on average. By flow cytometry analysis, we confirmed that the proportions of live sperms are significantly improved, which shows that the microfluidic chip is actually able to acquire live sperms. Finally, we use double-dye staining to verify the cell membrane of sperm are integral after collection.