Small-angle neutron scattering and Molecular Dynamics structural study of gelling DNA nanostars

Abstract

DNA oligomers with properly designed sequences self-assemble into well defined constructs. Here, we exploit this methodology to produce bulk quantities of tetravalent DNA nanostars (each one composed by 196 nucleotides) and to explore the structural signatures of their aggregation process. We report small-angle neutron scattering experiments focused on the evaluation of both the form factor and the temperature evolution of the scattered intensity at a nano star concentration where the system forms a tetravalent equilibrium gel. We also perform molecular dynamics simulations of one isolated tetramer to evaluate the form factor theoretically, without resorting to any approximate shape. The numerical form factor is found to be in very good agreement with the experimental one. Simulations predict an essentially temperature independent form factor, offering the possibility to extract the effective structure factor and its evolution during the equilibrium gelation.

arXiv comment9 pages, 5 figures

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Cited by in corpus (5)

• Microrheology of DNA Hydrogels
• Limiting the valence: advancements and new perspectives on patchy colloids, soft functionalized nanoparticles and biomolecules
• A primer on the oxDNA model of DNA: When to use it, how to simulate it and how to interpret the results
• Flexibility defines structure in crystals of amphiphilic DNA nanostars
• Hyperbranched DNA clusters