Tunable 2D diffusion of DNA nanostructures on lipid membranes

DNA nanotechnology facilitates the synthesis of biomimetic models for studying biological systems. This work uses lipid bilayers as platforms for two-dimensional single-particle tracking of the dynamics of DNA nanostructures. Three different DNA origami structures adhere to the membrane through hybridization with cholesterol-modified strands. Their two-dimensional diffusion coefficient is modulated by changing the concentration of monovalent and divalent salts and the number of anchors. In addition, the diffusion coefficient is tuned by targeting cholesterol-modified anchor strands with strand-displacement reactions. We demonstrate a responsive system with changing diffusivity by selectively displacing membrane-bound anchor strands. We also show the programmed release of origami structures from the lipid membranes.