DNA Nanostructures as Drug Carriers for Cellular Delivery

Drug delivery systems have been widely developed for enhancing target activity and improving drug functions. Liposomes, high-molecular polymer, gold nanoparticles and carbon nanomaterials, etc., are all the candidates of drug carriers. However, immunotoxicity, heterogeneity and low solubility generally exist and hamper their applications. As a kind of biological materials, DNA has its unique advantages in biomedical applications, including excellent biological compatibility and programmability. DNA nanostructures have been proved to possess high cellular uptake efficiency, which sheds new light on DNA-based drug delivery system. In this review, we summarize the influence factors of DNA nanostructure internalization efficiency, including cell lines, and the size and the shape of DNA nanoparticles. Uniformity of DNA nanostructures in appearance and properties ensures the stability in research, which makes DNA carriers stand out from other nanomaterials. Next, we focus on the functionalization of DNA carriers, which endows DNA nanostructures with the potential to construct integrated drug delivery platforms. We also discuss the internalization pathways of DNA nanostructures and their fate in cells. The deeply understanding about the endocytic pathways provides new sight for the further design strategy on changing the transportation routes of DNA carriers in cells. Finally, the challenges in further applications are discussed, and suggestions are proposed.