Binary superlattice design by controlling DNA-mediated interactions

TL;DR

This paper introduces a DNA-mediated interaction strategy to design binary superlattices with diverse 2D structures without relying on particle size differences, expanding the possibilities for material design.

Contribution

It presents a novel approach using tailored DNA strands to control interparticle interactions, enabling the creation of various 2D lattice structures independently of particle size.

Findings

Successfully created square, pentagonal, and hexagonal lattices.

Achieved compositional ordering in checkerboard, string, honeycomb, and Kagome patterns.

Demonstrated control over particle arrangement by adjusting mixture stoichiometry.

Abstract

Most binary superlattices created using DNA functionalization or other approaches rely on particle size differences to achieve compositional order and structural diversity. Here we study two-dimensional (2D) assembly of DNA-functionalized micron-sized particles (DFPs), and employ a strategy that leverages the tunable disparity in interparticle interactions, and thus enthalpic driving forces, to open new avenues for design of binary superlattices that do not rely on the ability to tune particle size (i.e., entropic driving forces). Our strategy employs tailored blends of complementary strands of ssDNA to control interparticle interactions between micron-sized silica particles in a binary mixture to create compositionally diverse 2D lattices. We show that the particle arrangement can be further controlled by changing the stoichiometry of the binary mixture in certain cases. With this approach, we demonstrate the abil- ity to program the particle assembly into square, pentagonal, and hexagonal lattices. In addition, different particle types can be compositionally ordered in square checkerboard and hexagonal - alternating string, honeycomb, and Kagome arrangements.