DNA nanostructures: design, functionalization, applications, and AI-driven advances.

DNA origami has revolutionized the field of nanomedicine by enabling the precise engineering of customizable nanostructures with programmable functionality. Using the reliable Watson-Crick base-pairing, scientists have created DNA structures that are compatible with living systems, precisely arranged, and responsive to changes. This article reviews a comprehensive examination over DNA origami, beginning with its conceptual origin and structural evolution, followed by a comparative classification of key nanostructures such as tiles, scaffolded origami, DNA bricks, and single-stranded origami. Advanced design methodologies supported by algorithmic tools, including caDNAno, MagicDNA, DAEDALUS, and oxDNA simulations, are also analyzed. Functionalization strategies are categorized into pre-and post-assembly approaches, highlighting chemical conjugation techniques for targeting and therapeutic loading. A significant focus is on stimuli-responsive systems that react with biological or physical factors such as pH, enzymes, redox microenvironment, and light. Clinical applications are explored through case studies in drug delivery, biosensing, immunotherapy, and gene regulation. Furthermore, challenges, including in vivo stability, immune response, and regulatory uncertainty have been critically assessed; while proposing future directions such as hybrid materials and personalized nanomedicine. Ultimately, a comprehensive overview of DNA origami mechanism evolves into clinically relevant nanoplatforms for precision therapy and diagnostics tools are provided.