Materials Science and Engineering Program, Colorado School of Mines, Golden, CO, USA.
Department of Applied Mathematics and Statistics, Colorado School of Mines, Golden, CO, USA.
Sci Adv. 2023 Apr 21;9(16):eadg0919. doi: 10.1126/sciadv.adg0919.
Microbot (μbot)-based targeted drug delivery has attracted increasing attention due to its potential for avoiding side effects associated with systemic delivery. To date, most μbots are rigid. When rolling on surfaces, they exhibit substantial slip due to the liquid lubrication layer. Here, we introduce magnetically controlled soft rollers based on Pickering emulsions that, because of their intrinsic deformability, fundamentally change the nature of the lubrication layer and roll like deflated tires. With a large contact area between μbot and wall, soft μbots exhibit tractions higher than their rigid counterparts, results that we support with both theory and simulation. Upon changing the external field, surface particles can be reconfigured, strongly influencing both the translation speed and traction. These μbots can also be destabilized upon pH changes and used to deliver their contents to a desired location, overcoming the limitations of low translation efficiency and drug loading capacity associated with rigid structures.
基于微机器人（μbot）的靶向药物输送由于其避免与全身输送相关的副作用的潜力而引起了越来越多的关注。迄今为止，大多数 μbot 都是刚性的。当在表面上滚动时，由于液体润滑层的存在，它们会产生大量滑动。在这里，我们介绍了基于 Pickering 乳液的磁控软辊，由于其固有的可变形性，它们从根本上改变了润滑层的性质，并像瘪胎一样滚动。由于 μbot 和壁之间的大接触面积，软 μbot 表现出的牵引力高于其刚性对应物，我们通过理论和模拟都支持这一结果。通过改变外部磁场，表面颗粒可以重新配置，这强烈影响着平移速度和牵引力。这些 μbot 也可以在 pH 值变化时失稳，并将其内容物输送到所需的位置，克服了与刚性结构相关的低传输效率和药物负载能力的限制。
