Conformational Nature of DNA–Grafted Chains on Spherical Gold Nanoparticles

Published

September 10, 2016

Author(s)

Jack F. Douglas, Fernando Vargas-Lara

Abstract

We investigate the conformational state of a simple, coarse–grained molecular model for single–stranded DNA chains (ss-DNA) grafted onto spherical symmetric gold nanoparticles (NPs) and of the grafted layer as a whole by molecular dynamic simulations. In particular, we compare the radius of gyration (Rg) of an individual grafted chain to its value in solution and we use path–integration to estimate the change delta Rh of the hydrodynamic radius of ssDNA–grafted NPs (Rh) from the hydrodynamic radius of the bare gold NP core (R = 5:0 nm) for a range of grafted chains (N), chain lengths (L), and persistence lengths (lp) relevant to experimental studies of these NPs. We find the ssDNA chain size is not greatly perturbed from its free solution value so that the molecular cartoon of a brush–like layer involving highly extended ssDNA chains is an unrealistic model of the interfacial structure of ssDNA–grafted NPs under the solution conditions normally investigated.

Citation

AIP Conference Proceedings

Pub Type

Journals

Keywords

gold nanoparticle, single-stranded DNA, chain grafting, conformation of grafted chain layer, radius of gyration, hydrodynamic radius

Citation

Douglas, J. and Vargas-Lara, F. (2016), Conformational Nature of DNA–Grafted Chains on Spherical Gold Nanoparticles, AIP Conference Proceedings (Accessed November 16, 2025)