Mesoscale hierarchical helical structures with diverse functions are abundant in nature. Here
we show how spontaneous helicity can be induced in a synthetic polymeric nanobristle
assembling in an evaporating liquid. We use a simple theoretical model to characterize the
geometry, stiffness, and surface properties of the pillars that favor the adhesive self-organization
of bundles with pillars wound around each other. The process can be controlled to yield highly
ordered helical clusters with a unique structural hierarchy that arises from the sequential assembly
of self-similar coiled building blocks over multiple length scales. We demonstrate their function
in the context of self-assembly into previously unseen structures with uniform, periodic patterns
and controlled handedness and as an efficient particle-trapping and adhesive system.