Scientists have crafted a robust material by merging two surprising components: DNA and glass. Operating at the nanolevel gives researchers detailed insight and accuracy in producing and studying materials.
On larger scales and even in natural environments, many materials face issues like defects or impurities, affecting their intricate design. These imperfections might lead them to break when stressed.
Especially with most glass varieties, this results in their perception as delicate. Teams from Columbia University, the University of Connecticut, and the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory succeeded in producing a refined version of glass.
They then coated unique DNA fragments with it, producing a substance stronger than steel and impressively light. It’s rare to find materials with both these attributes and ongoing studies might unlock innovative engineering and defense uses.
Their findings were shared in the Cell Reports Physical Science journal. In living entities, DNA, short for deoxyribonucleic acid, holds the biological data that guides organism cells on development, growth, and multiplication.
DNA’s composition belongs to polymers, a robust and stretchy category of materials, which encompasses plastics and rubber. Their durability and straightforwardness have captured the attention of materials researchers, leading to several fascinating projects.
For years, Oleg Gang, a material researcher at the Center for Functional Nanomaterials (CFN), a DOE Office of Science User Facility located at Brookhaven Lab, and also a faculty at Columbia University, has tapped into the distinctive attributes of DNA for material creation, yielding multiple breakthroughs.
Such cutting-edge methods have spurred a plethora of revolutionary uses, ranging from medication delivery to advanced electronics.
Previously, Gang collaborated with the study’s main author, Brookhaven postdoctoral investigator Aaron Michelson, on a project utilizing DNA structures to set the groundwork for new materials. DNA units operate in a captivating manner.
Individual nucleotides, the foundational units of nucleic acids like DNA and RNA, govern the connections between corresponding sequences. Their accurate bonding technique empowers researchers to devise methods to mold DNA into particular forms, labeled “origami”, drawing inspiration from traditional Japanese paper art.
These DNA formations act as nanoscale components that can be directed to “self-assemble” via designated DNA connections. This facilitates the spontaneous emergence of well-organized structures using these DNA origami units.
Subsequently, these components interconnect to produce a bigger grid—a formation with a consistent pattern. This methodology enables the creation of ordered 3D nanomaterials from DNA, and the incorporation of non-organic nanoparticles and proteins, as evidenced in prior research by the team.
With mastery over this assembly technique, Gang, Michelson, and their collaborators ventured to see the outcomes when such bio-molecular structure was employed to craft silica structures that retain the foundational design.
For his significant contributions in this domain, Michelson was honored with the Robert Simon Memorial Award at Columbia University. His DNA framework studies span various aspects and potential uses, from mechanical attributes to superconducting capabilities.
Mirroring the constructs he has developed, Michelson’s endeavors continue to evolve, incorporating more insights from these thrilling trials. A subsequent step in the creation process drew inspiration from biomineralization—the process by which certain live tissues mineralize to become tougher, akin to bones.
Using a slender silica glass layer, around 5 nm or merely a few hundred atoms in thickness, they enveloped the DNA structures, retaining inner voids, and ensuring the resulting substance remains ultra-light.
At this diminutive scale, glass isn’t vulnerable to flaws or imperfections, bestowing a sturdiness uncommon in larger glass pieces susceptible to fracturing. To assess this material’s resilience, specialized instruments were essential.
Simple tests can determine an object’s robustness. Probing, pressing, and leaning on items to monitor reactions can provide insight. Do they flex, make noises, collapse, or resist the applied force?
Such intuitive tests can gauge an item’s durability even without precise measuring tools. But how does one exert force on something microscopic? During compression, or indentation, of the sample, scientists can capture metrics and assess mechanical characteristics.
They can then observe the material’s behavior when compression is relieved and the specimen reverts to its initial state. Any fractures or structural failures are meticulously noted. In testing, it was revealed that the DNA-glass lattice was quadruple the strength of steel!
Intriguingly, its mass was roughly one-fifth. Though some materials are known to be resilient and comparatively light, such an extent has never been observed. Such an approach wasn’t always accessible at CFN.
More development and research are required before envisioning the myriad potential uses of such a material. Nonetheless, the discoveries have material scientists abuzz about the future.
The group aims to investigate other materials like carbide ceramics, potentially stronger than glass, to understand their characteristics. This might pave the way for even tougher, lightweight materials.
Even though he’s early in his professional journey, Michelson has already marked significant milestones and is enthusiastic about advancing his investigations.
