An efficient biomimetic assembly of a macroscopic polyhedral shell from identical subunits

A model system is presented for efficiently assembling a convex polyhedral shell from identical subunits under agitation. The system draws upon two elements of viral assembly. First, the subunits have built-in instructions for shell formation. Second, a flexible template—equivalent to the viral genome—is used to capture the subunits and then orchestrate their assembly into the final structure. Capturing the subunits on the template was achieved by shaking them (1.5 shell equivalents) onto the template lying extended in a shallow planar cavity. Agitating the template/subunit complex in a tumbler resulted in it rapidly folding (seconds). The complete assembly process, which is mediated by reversible magnetic bonds, took approximately 10 s to 5 min, and always resulted in the formation of a closed shell. When the subunits were agitated in the tumbler in the absence of template, a complete shell was produced only 10% of the time. Although the model system as demonstrated here generates a macroscopic dodecahedral shell, the principle could be applied to other polyhedra containing larger numbers of subunits and the system as a whole automated and miniaturised to build optically interesting structures or autonomous electronic devices.