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arXiv · 2309.04632

Limits of economy and fidelity for programmable assembly of size-controlled triply-periodic polyhedra

Abstract

We propose and investigate an extension of the Caspar-Klug symmetry principles for viral capsid assembly to the programmable assembly of size-controlled triply-periodic polyhedra, discrete variants of the Primitive, Diamond, and Gyroid cubic minimal surfaces. Inspired by a recent class of programmable DNA origami colloids, we demonstrate that the economy of design in these crystalline assemblies -- in terms of the growth of the number of distinct particle species required with the increased size-scale (e.g. periodicity) -- is comparable to viral shells. We further test the role of geometric specificity in these assemblies via dynamical assembly simulations, which show that conditions for simultaneously efficient and high-fidelity assembly require an intermediate degree of flexibility of local angles and lengths in programmed assembly. Off-target misassembly occurs via incorporation of a variant of disclination defects, generalized to the case of hyperbolic crystals. The possibility of these topological defects is a direct consequence of the very same symmetry principles that underlie the economical design, exposing a basic tradeoff between design economy and fidelity of programmable, size controlled assembly.

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Carlos M. Duque, Douglas M. Hall, Botond Tyukodi, Michael F. Hagan, Christian D. Santangelo, Gregory M. Grason. 2023-09-08. Limits of economy and fidelity for programmable assembly of size-controlled triply-periodic polyhedra. https://arxiv.org/abs/2309.04632

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