Customizable silicification of DNA origami nanostructures

Abstract

The silicification of DNA origami nanostructures offers a powerful strategy for enhancing their mechanical stability and resistivity against detrimental environmental conditions. In the past years, several studies have investigated different aspects of the silica coating procedure, leading to several different silicification protocols. Until now, the silica coating generally served as a protective layer or as the base for the further deposition of inorganic materials. However, it did not carry any additional functionality itself. Here, we present two different approaches for the customization of the silica coating on DNA origami nanostructures. Firstly, we developed a custom synthesized silica precursor carrying a fluorescein molecule to endow the silica coating of both DNA origami monomers and crystals with fluorescence and show the applicability of this novel silicification for the stabilization and tracking of DNA origami nanostructures intracellularly. Secondly, we employ a silica precursor containing a disulfide bridge to develop a silica coating that is dissolvable in a reducing environment. We anticipate that the results presented in this study will expand the toolbox of silicification in DNA nanotechnology and will further pave the way towards applications in drug delivery and material science.