Biomolecular polymerization motors are biochemical systems that use supramolecular (de-)polymerization to convert chemical potential into useful mechanical work. With the intent to explore new chemomechanical transduction strategies, here we show a synthetic molecular system that can generate forces via the controlled disassembly of self-organized molecules in a crystal lattice, as they are freely suspended in a fluid. An amphiphilic monomer self-assembles into rigid, high-aspect-ratio microcrystalline fibres. The assembly process is regulated by a coumarin-based pH switching motif. The microfibre crystal morphology determines the monomer reactivity at the interface, resulting in anisotropic etching. This effect exerts a directional pulling force on microscopic beads adsorbed on the crystal surface through weak multivalent interactions. We use optical-tweezers-based force spectroscopy to extract mechanistic insights into this process, quantifying a stall force of 2.3 pN (±0.1 pN) exerted by the ratcheting mechanism produced by the disassembly of the microfibres.

生物分子聚合电机是利用超分子（去）聚合将化学势转化为有用的机械功的生化系统。为了探索新的化学机械转导策略，我们在这里展示了一个合成分子系统，该系统可以通过控制分解晶格中的自组织分子来产生力，因为它们可以自由悬浮在流体中。两亲性单体自组装成刚性、高纵横比的微晶纤维。组装过程由基于香豆素的 pH 切换基序调节。微纤维晶体形态决定了界面处的单体反应性，从而产生各向异性蚀刻。这种效应通过微弱的多价相互作用对吸附在晶体表面的微观微珠施加定向拉力。我们使用基于光镊的力谱来提取对这一过程的机理见解，量化了由分解超细纤维产生的棘轮机构施加的 2.3 pN （±0.1 pN） 的失速力。