Spiraling-Based Structural DNA Nanotechnology to Regulate the Orientation of Sticky Ends for Intelligent Assembly of In Vivo Targeting DNA Nanostructures

Homogeneous DNA nanostructures made entirely of DNA strands have attracted great attention in the biomedical and nanomedical fields. However, the intrinsic vulnerability of native nucleic acids to enzymatic degradation limits their practical utility in real-world applications. In this contribution, spiraling-based structural DNA (SSD) nanotechnology is demonstrated to construct an intelligent nuclease-resistant tumor cell-targeting aptamer-functionalized DNA nanowire (ADW) for in vivo long-circulating tumor fluorescence imaging. ADW not only has the assembly efficiency of up to 100% and can distinguish positive target cells from negative nontarget cells but also possesses 4.0 times enhanced specific cellular internalization ability. For ADW with vertically aligned aptamers (A-VDW), no obvious enzymatic degradation is detected after 72 h systemic postadministration, validating that the in vivo stability of A-VDWs is enhanced by over 800 times. In addition, via using a palindromic oligonucleotide, SSD technology-based ADW is employed for the further assembly of two-dimensional (2D) and three-dimensional (3D) DNA architectures, during which only five DNA components are needed. As a proof of concept, SSD technology-based DNA assembly is expected to offer an unparalleled opportunity for the development of next-generation DNA architectures, thereby resolving the existing bottleneck encountered in in vivo applications and playing an important role in cancer diagnosis and therapy.