Colloidal joints with designed motion range and tunable joint flexibility

Abstract

The miniaturization of machines towards the micron and nanoscale requires the development of joint-like elements that enable and constrain motion. We present a facile method to create colloidal joints, that is, anisotropic colloidal particles functionalized with surface mobile DNA linkers that control the motion range of bonded particles. We demonstrate quantitatively that we can control the flexibility of these colloidal joints by tuning the DNA linker concentration in the bond area. We show that the shape of the colloidal joint controls the range of motion of bonded particles through a maximisation of the bond area. Using spheres, cubes, and dumbbells, we experimentally realize spherical joints, planar sliders, and hinges, respectively. Finally we demonstrate the potential of the colloidal joints for programmable bottom-up self-assembly by creating flexible colloidal molecules and colloidal polymers. The reconfigurability and motion constraint offered by our colloidal joints make them promising building blocks for the development of switchable materials and nanorobots.

Programmable interactions with biomimetic DNA linkers at fluid membranes and interfaces

“…Indeed, the unimpeded pivoting of colloidal junctions enable the relaxation of the aggregates towards a closepacked hexagonal lattice maximising particle-particle contacts [15]. The properties of "colloidal joints" formed from bilayer-coated particles, including their range of motion and flexibility, were then systematically characterised by Chakraborty et al [105]. By studying the interactions between cubic and spherical particles, the authors also demonstrated the effect of surface curvature.…”

Synthesis of Colloidal Molecules: Recent Advances and Perspectives

“…Another series of experiments concern the use of colloids functionalized with surface mobile DNA linkers as building blocks . It was possible to create flexible CMs which are physically stable but reorganise in permanence at high speed (Figure a) . The sequence programmable folding of a plasmid by DNA staple strands, also called DNA origami, which allows one to design nanoscale DNA architectures with extensive shape control, has also been used to template the organization of DNA coated particles.…”

“…[47,48] It was possible to create flexible CMs which are physically stable but reorganise in permanencea th igh speed (Figure 3a). [49] The sequence programmablef olding of ap lasmidb yD NA Figure 3. a) Schematic representation and confocal microscopy images of flexible CMs made from particles with mobile DNA linkers.…”

“…a) Schematic representation and confocal microscopy images of flexible CMs made from particles with mobile DNA linkers. [49] b) Scheme, cryoEM imagesand 3D structuralm odel reconstructed from the cryoEM images of methane-like CMs obtained by using at etrahedral DNA cage. [52] c) TEM images of AX 3 Y-,A X 2 Y 2 ,AXY 3 -and AWXYZ-like CMs (scaleb ars:1 00 nm).…”

“…[73] Adapted with permission from Refs. [49], [52], [ 67], [69], [ 70] and [73],copyright RSC 2017, ACS 2015,Wiley-VCH2 018,N PG 2017, NPG 2012and NAS 2018. staple strands, also called DNA origami, which allows one to design nanoscale DNA architectures with extensive shape control, has also been used to template the organizationo fD NA coated particles. One can place ag old nanoparticle in the center of an origami to create square-shaped or cross-shaped CMs.…”