Ultrathin Silica Coating of DNA Origami Nanostructures

The DNA origami technique has emerged as one of the most versatile bottom-up nanofabrication methods due to its ability to construct well-defined complex three-dimensional nanostructures and guide assembly of functional nanoscale objects with unprecedented precision, high yields, and controlled stoichiometry. Nonetheless, limited compatibility with biologically relevant fluids and typical solvents utilized in nanofabrication often restricts applications of DNA origami-based assemblies and devices. Here we present an approach for coating DNA origami structures with silica. By careful adjustment of experiment parameters, we achieved reproducible growth of ultrathin silica shell in solution without agglomeration or deformation of DNA origami structures. The silica-coated structures are stable in water and exhibit an increased resistivity to nuclease-mediated degradation. In addition, the coated structures preserve their structural integrity in polar organic solvents. We anticipate that our results will aid further advancement of DNA origami techniques as the nanofabrication method.