Programmed self-assembly of DNA origami nanoblocks into anisotropic higher-order nanopatterns

Anisotropic nanopatterns have potentials in constructing novel plasmonic structures which have various applications in such as super-resolution microscopy, medicine, and sensors. However, it remains challenging to build big anisotropic nanopatterns that are suitable for big noble metal nanoparticles. Herein, we report a simple and reliable strategy for constructing DNA origami-based big anisotropic nanopatterns with controlled size and shape, nanoscale resolution, and fully addressability. Two kinds of basic DNA origami nanoblocks - cross-shaped and rectangular DNA origami units were used. We have demonstrated that by encoding nanoblocks' edges, anisotropic higher-order nanopatterns, such as dimer, trimer, tetramer and mini "windmill" like pentamer nanopatterns could be constructed. To show the potential use as template to direct the assembly of anisotropic nanoparticles arrays, a proof of concept work was conducted by anchoring streptavidin nanoparticles on the "windmill" template to form a chiral array. Significantly, these nanopatterns have the sizes of hundreds of nanometers, which are in principle also suitable for big noble metal nanoparticles arrays.