Colloidal Flying Carpets

TL;DR

This paper reports the discovery of unique floating crystalline monolayers formed by colloids coated with long double-stranded DNA, revealing new self-assembly behaviors with potential applications in layered colloidal crystal fabrication.

Contribution

It introduces a novel self-assembly phenomenon where long DNA-coated colloids form floating monolayers, expanding understanding of colloidal assembly mechanisms.

Findings

Colloids with long DNA can form floating crystalline monolayers.

The structures enable potential layered colloidal crystal fabrication.

Self-assembly is driven by DNA length and coating properties.

Abstract

DNA plays a special role in polymer science not just because of the highly selective recognition of complementary single DNA strands but also because bacteria can express DNA chains that are very long yet perfectly monodisperse. The latter reason makes long DNA molecules widely used as model systems in polymer science. Here, we report the unusual self-assembly that takes place in systems of colloids coated with very long double-stranded DNA. In particular, we find that colloids coated with such long DNA can assemble into unique floating crystalline monolayers. Floating colloidal structures have potentially interesting applications as such ordered structures can be assembled in one location and then deposited somewhere else. This would open the way to the assembly of multi-component, layered colloidal crystals.