High DNA density localizes RNase H near its target. (A) Proposed intermediate with RNase H and target bound to the NP. (B) DLS measurements of particle diameter at multiple RNase H concentrations. (C) RNase H inhibition by ssDNA when not particle bound. Each point represents the normalized initial rate of substrate degradation. The error bars represent the standard error from three independent experiments. (D, E) Schematic of free (D) and nanoparticle bound (E) substrates. As in previous schemes, DNA, RNA, and RNase H are depicted in black, green and blue respectively.