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根据微流体系统中的风力学和天体学进行合格精子选择
Nima Ahmadkhani1, Maryam Saadatmand1, Somaieh Kazemnejad2
1Department of Chemical and Petroleum Engineering, Sharif University of Technology, 11155-9465, Tehran, Iran.
Biomedical engineering letters
|October 24, 2023
概括
这项研究开发了一种用于分离精子的微流体系统,模仿女性生殖道. 通过使用rheotaxis和tighmotaxis,鼻状几何学增强了辅助生殖技术的精子质量.
科学领域:
- 生物医学工程 生物医学工程
- 生殖生物学 生殖生物学
- 微流体学 微流体学
背景情况:
- 辅助生殖技术 (ART) 需要高质量的精子.
- 目前的精子分离方法面临着局限性.
- 微流体系统提供了一种有希望的方法来模仿女性生殖道 (FRT),以改善精子选择.
研究的目的:
- 设计和制造一种微流体系统,用于被动的精子分离.
- 为了研究rheotaxis和tighmotaxis对精子质量的联合影响.
- 为了确定最佳的微通道几何,以提高精子分离.
主要方法:
- 基于PDMS的微流体系统的制造,具有四种几何形状:线性,方形,形和正弦形.
- 利用流动动 (流动诱导的运动) 和tighmotaxis (跟随墙壁的行为) 进行被动分离.
- 使用精子跟踪 (ImageJ),运动性测试 (CASA软件) 和形态测试 (帕帕尼科拉或超快染色) 评估精子功能.
主要成果:
- 所有测试的微通道几何结构都产生了100%的运动精子.
- 非线性几何形状 (正弦形,齐克扎克形,方形) 在分离渐进,高质量的精子方面比线性几何形状更有效.
- 形几何学表现出最高的增强,导致分离的精子具有34.7%的正常形态,100%的运动性和100%的生存能力.
- 方形和齐格扎格几何形状的死区阻碍了精子向出口的进展.
结论:
- 精子位置的定期变化,受壁相互作用和流动的影响,对于高质量的精子分离至关重要.
- 状微通道几何是精子分离最有效的设计,显著提高了形态质量.
- 模仿FRT特征的微流体系统,特别是形设计,代表了辅助生殖技术的重大进步.
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