Nucleic Acid‐Based Molecular Machines for Biological Applications

Molecular machines, constructed from molecules with specific functions through the molecular engineering, requires the development of a general assembly strategy that is crucial for the design and fabrication molecular machines. The precise and programmable characteristics of Watson–Crick base‐pairing allow for the accurate construction of DNA nanostructures with diverse geometries. Furthermore, DNA itself exhibits various functionalities, such as DNAzymes and aptamers for identification, and unique structures like G‐quadruplexes and i‐motifs for environmental stimulus response. With the significant advancements in DNA nanotechnology, DNA is increasingly being recognized as a versatile building block for molecular machines design. In this review, a comprehensive overview of DNA nanostructures, such as 2D origami, which are subsequently assembled into molecular machines is provided. Their classification of DNA‐based molecular machines is discussed and their biological applications, such as biosensing, targeted therapy, and molecular circuits are explored. Additionally, future directions and challenges in this rapidly evolving field are outlined.