Engineering Ultrasoft Interactions in Stiff All-DNA Dendrimers by Site-Specific Control of Scaffold Flexibility

Author(s)
Nataša Adžić, Clemens Jochum, Christos N. Likos, Emmanuel Stiakakis
Abstract

A combined experimental and theoretical study of the structural correlations in moderately concentrated suspensions of all-DNA dendrimers of the second generation (G2) with controlled scaffold rigidity is reported here. Small-angle X-ray scattering experiments in concentrated aqueous saline solutions of stiff all-DNA G2 dendritic constructs reveal a novel anomalous liquid-like phase behavior which is reflected in the calculated structure factors as a two-step increase at low scattering wave vectors. By developing a new design strategy for adjusting the particle's internal flexibility based on site-selective incorporation of single-stranded DNA linkers into the dendritic scaffold, it is shown that this unconventional type of self-organization is strongly contingent on the dendrimer's stiffness. A comprehensive computer simulation study employing dendritic models with different levels of coarse-graining, and two theoretical approaches based on effective, pair-potential interactions, remarkably confirmed the origin of this unusual liquid-like behavior. The results demonstrate that the precise control of the internal structure of the dendritic scaffold conferred by the DNA can be potentially used to engineer a rich palette of novel ultrasoft interaction potentials that could offer a route for directed self-assembly of intriguing soft matter phases and experimental realizations of a host of unusual phenomena theoretically predicted for ultrasoft interacting systems.

Organisation(s)
Computational and Soft Matter Physics
External organisation(s)
Technische Universität Wien, University of Belgrade, Forschungszentrum Jülich
Journal
Small
Volume
20
No. of pages
12
ISSN
1613-6810
DOI
https://doi.org/10.1002/smll.202308763
Publication date
01-2024
Peer reviewed
Yes
Austrian Fields of Science 2012
103015 Condensed matter, 102009 Computer simulation
Keywords
ASJC Scopus subject areas
Biotechnology, General Chemistry, Biomaterials, General Materials Science, Engineering (miscellaneous)
Portal url
https://ucrisportal.univie.ac.at/en/publications/92a698f5-21c8-454c-9f34-695976bf123e