对非磁性生物体的磁性控制
Ahmed Al Harraq1, Min Feng2, Hashir M Gauri1
1Cain Department of Chemical Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, United States.
ACS applied materials & interfaces
|March 26, 2024
概括
研究人员开发了一种使用磁场和氧化铁纳米粒子控制非磁性生物的新方法. 这种技术允许微生物的精确时空组织,而无需进行遗传修饰或磁性杂交.
科学领域:
- 生物物理学的生物物理.
- 微流体学 微流体学
- 机器人技术 机器人技术 机器人技术
背景情况:
- 生物为微机器人设计提供了独特的传感和通信能力.
- 目前用于微机器人控制的磁性杂交方法是生物特异的,缺乏通用性.
- 对非磁性生物实体的外部控制仍然是一个重大挑战.
研究的目的:
- 提出和验证一种新的,可通用的方法来控制使用外部磁场的非磁性生物.
- 为了研究负磁静电学和磁泳术用于生物操纵的原理.
- 为了使生物微生物的时空组织没有侵入性程序.
主要方法:
- 在Fe3O4纳米粒子悬浮中分散模型生物 (C. elegans幼虫,鞭状细菌,精子,成年C. elegans).
- 应用均和梯度磁场来操纵生物-纳米粒子混合物.
- 在不同的磁场条件下分析生物体的反应,包括对齐和运动.
主要成果:
- 统一的磁场通过外部扭矩诱导了生物的对齐.
- 渐变的磁场产生了负磁电力,将生物从磁铁中排斥出来.
- 在C. elegans幼虫和鞭状细菌中,成功控制了位置和方向.
- 由于固有的生物力量,活体精子和成年C. elegans的控制有效性降低了.
结论:
- 通过使用磁场和纳米粒子来控制非磁性生物的非侵入性方法已经建立.
- 这种方法克服了形态特异性磁性杂交技术的局限性.
- 这些发现为开发可控制的活生生的微生物机器人铺平了道路,因为它们能够实现精确的时空组织.
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