Classical nucleation and growth of DNA-programmed colloidal crystallization

TL;DR

This study uses microfluidics to analyze DNA-coated colloid crystallization, validating classical nucleation and growth theories and enabling the design of protocols for large, functional colloidal crystals.

Contribution

It provides a detailed quantitative analysis of the crystallization dynamics of DNA-coated colloids, validating classical theories with modifications, and demonstrates protocols for controlled crystal assembly.

Findings

Classical theories accurately predict nucleation and growth rates after modifications.

Temperature and concentration critically influence crystallization kinetics.

Protocols developed enable assembly of large, structurally colored colloidal crystals.

Abstract

DNA-coated colloids can self-assemble into an incredible diversity of crystal structures, but applications of this technology are limited by poor understanding and control over the dynamical crystallization pathways. To address this challenge, we use microfluidics to quantify the self-assembly dynamics of DNA-programmed colloidal crystals, from thermally-activated nucleation through reaction-limited and diffusion-limited phases of crystal growth. Our detailed measurements of the temperature and concentration dependence of the kinetics at all stages along the crystallization pathway provide a stringent test of classical theories of nucleation and growth. After accounting for the finite rolling rate of micrometer-sized DNA-coated colloids, we find that modified versions of these classical theories quantitatively predict the absolute nucleation and growth rates. We conclude by applying our model to design and demonstrate protocols for assembling large single crystals, including crystals with pronounced structural coloration, an essential step in the creation of next-generation functional materials from colloids.