KCS

We design a DNA-based Brownian motor for directional transport of positively charged nanoparticles along a single, long double-stranded DNA (dsDNA) with elaborately designed flexibility variation. To prove its realization, we first investigate the bending of intrinsically rigid dsDNA by binding with a cationic nanoparticle, using the coarse-grained molecular dynamics simulations. An electric charge of the nanoparticle and the sequence-dependent flexibility of dsDNA are varied to elucidate the competitive effects of intrinsic rigidity of dsDNA and electrostatic interactions between charged dsDNA and a nanoparticle. We prove that the nanoparticle wrapped around by dsDNA rolls over the dsDNA towards more flexible region of the dsDNA. This work suggests that dsDNA molecules with elaborately designed flexibility variation can be used as a molecule-scale guide for spatial and dynamic control of nanoparticles for future applications.