Synthetic Strategies Toward DNA-Coated Colloids that Crystallize

Abstract

We report on synthetic strategies to fabricate DNA-coated micrometer-sized colloids that, upon thermal annealing, self-assemble into various crystal structures. Colloids of a wide range of chemical compositions, including poly(styrene), poly(methyl methacrylate), titania, silica, and a silica-methacrylate hybrid material, are fabricated with smooth particle surfaces and a dense layer of surface functional anchors. Single-stranded oligonucleotides with a short sticky end are covalently grafted onto particle surfaces employing a strain-promoted alkyne-azide cycloaddition reaction resulting in DNA coatings with areal densities an order of magnitude higher than previously reported. Our approach allows the DNA-coated colloids not only to aggregate upon cooling but also to anneal and rearrange while still bound together, leading to the formation of colloidal crystal compounds when particles of different sizes or different materials are combined.

Entropy Stabilizes Floppy Crystals of Mobile DNA-Coated Colloids

“…These ssDNA tails serve as "sticky ends" that bind specifically to other colloids coated with ssDNA tails of complementary sequence, which offers a novel way of manipulating the self-assembly of colloidal particles [2,3]. By using DNA-coated colloids (DNACCs), a number of ordered crystals [4][5][6][7][8][9][10] and selfassembled "colloidal molecules" [11] have been obtained in experiments, while the self-assembly mechanism of DNACCs is still not well understood [9,12,13]. For example, the diffusionless transformation from a floppy crystal to the other compact crystal has been observed in experimental systems while the underlying mechanism remains not fully resolved [13].…”

Using DNA strand displacement to control interactions in DNA-grafted colloids

“…[34][35][36] We also foresee no obstacles to integrating strand-displacement reactions into the emulsion systems with the mobile DNA strands demonstrated by Brujic and coworkers. 37,38 8 Methods and materials…”

Programmable Atom Equivalents: Atomic Crystallization as a Framework for Synthesizing Nanoparticle Superlattices

“…NPs with luminescent properties (cadmium selenide, cadmium telluride, and zinc sulfide quantum dots), magnetic properties (iron oxide), and catalytic properties (palladium and platinum) have all also been demonstrated. The breadth of available PAE core sizes has increased with the DNA functionalization of other oxide cores (silica and titania) and polymer spheres (poly(styrene) (PS), poly(methyl methacrylate) (PMMA), and 3‐(trimethoxysilyl)propyl methacrylate (TPM)). Even metal–organic‐frameworks (MOFs) have been shown as a suitable PAE core material.…”