LAUSR

Due to high programmability and good biocompatibility, DNA has been recognized as a powerful building block for engineering of sophisticated nanostructures for different purposes. Herein, we present the first example of bead-string-shaped DNA nanostructure (BS-nanowire) with long-range structural order for in vivo bioimaging and targeting drug delivery. BS-nanowire is assembled from DNA tetrahedron units with precise nanometer-scale spatial control, capable of accommodating chemotherapeutic agents with high payload capacity (1204 binding sites) as well as possessing a 60-fold enhanced binding affinity for target cells. Confocal fluorescence imaging and in vivo experiments on CEM subcutaneous tumor-bearing mice show that specific bioimaging of living cells, even systemic delivery of drugs into internal tumor organs and tissues, were accomplished, thereby achieving an efficient inhibition of tumor growth in xenograft model without systemic toxicity. BS-nanowires possess the potential in vivo applications in accurate diagnosis and targeted therapy for human cancer.