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arXiv · 2507.04985

Stochastic size control of self-assembled filaments

Maximilian C. Hübl·Carl P. Goodrich
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Abstract

Controlling the size and shape of assembled structures is a fundamental challenge in self-assembly, and is highly relevant in material design and biology. Here, we show that specific, but promiscuous, short-range binding interactions make it possible to economically assemble linear filaments of user-defined length. Our approach leads to independent control over the mean and width of the filament size distribution and allows us to smoothly explore design trade-offs between assembly quality (spread in size) and cost (number of particle species). We employ a simple hierarchical assembly protocol to minimize assembly times, and show that multiple stages of hierarchy make it possible to extend our approach to the assembly of higher-dimensional structures. Our work provides a simple and experimentally straightforward solution to size control that is immediately applicable to a broad range of systems, from DNA origami assemblies to supramolecular polymers and beyond.

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Maximilian C. Hübl, Carl P. Goodrich. 2025-07-07. Stochastic size control of self-assembled filaments. https://arxiv.org/abs/2507.04985

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