- DNA nanostructures are engineered assemblies of DNA molecules that are designed to form precise, predictable shapes and patterns at the nanoscale.
- Unlike the traditional role of DNA as a carrier of genetic information, in nanotechnology DNA is used as a structural material. This is possible because of the molecule’s highly specific base-pairing rules—adenine pairs with thymine, and cytosine with guanine—which allow scientists to program the self-assembly of DNA into intricate and stable architectures. These nanostructures have become a powerful tool in the design of nanoscale devices, sensors, and drug delivery systems.
- The concept of DNA as a building material began gaining traction in the 1980s when Nadrian Seeman proposed using DNA to create lattice-like frameworks for organizing other molecules. Since then, the field has rapidly evolved. One of the most influential developments was the advent of DNA origami, introduced by Paul Rothemund in 2006. In this technique, a long single-stranded DNA molecule (typically from a virus) is folded into a specific shape using dozens or hundreds of short “staple” strands that bind to designated sites. This method enables the creation of complex two- and three-dimensional structures such as boxes, tubes, gears, and even nanorobots with moving parts.
- There are several classes of DNA nanostructures, including tiles, lattices, cages, and polyhedra, each with unique properties and applications. DNA tiles are modular units that can assemble into larger periodic structures, while 3D polyhedral DNA structures can encapsulate and protect cargo, such as drugs or enzymes, making them suitable for targeted drug delivery. These nanostructures are not only customizable in shape and size, but also highly programmable. By including molecular recognition elements, DNA nanostructures can be designed to respond to specific chemical signals or environmental stimuli, enabling dynamic behavior such as opening, closing, or changing shape.
- In addition to static shapes, dynamic DNA nanostructures are being developed to perform mechanical functions. For example, DNA walkers are nanoscale machines that move along a track, powered by chemical reactions such as strand displacement. These constructs mimic biological motors and have potential applications in targeted transport and nanoscale assembly lines. Another area of advancement involves DNA hydrogels—networks of DNA strands that form a gel-like material with applications in tissue engineering and biosensing.
- The applications of DNA nanostructures are vast and growing. In biomedicine, they are used to deliver drugs or genetic material to specific cells, minimizing side effects and improving efficacy. In biosensing, DNA nanostructures can detect specific molecules with high sensitivity and selectivity, making them valuable for diagnostics. In materials science, they serve as scaffolds for arranging nanoparticles, proteins, or other functional elements with nanometer precision. This makes them useful for constructing nanoelectronic circuits, photonic devices, and even quantum systems when combined with other nanotechnologies.
- Despite the impressive progress, challenges remain in making DNA nanostructures practical for widespread use. Stability in physiological conditions, large-scale manufacturing, and integration with other materials are active areas of research. Nevertheless, ongoing advances in synthetic biology, automation, and computational design are rapidly improving the reliability and functionality of DNA-based nanotechnology.
