Scientists have discovered that DNA molecules can self-organize into adhesive patches when given instructions. These findings provide a proof of concept for an innovative method to create materials with well-defined connectivity among the particles.
Proceedings of the National Academy of Sciences reports the work.
Jasna Brjic, a New York University professor and one of the researchers, said that it was possible to program particles to create customized structures with custom properties. While cranes, drills and hammers are still controlled by humans when building buildings, this research shows how physics can be used to create smart materials that 'know how to assemble."
Scientists have been searching for a way to allow molecules to self-assemble for a long time and have made many breakthroughs. These tiny particles can self-assemble using a preprogrammed set of bonds, but this is a less well-developed method.
Brujic, her co-workers, Angus McMullen (a postdoctoral researcher at NYU's Department of Physics) and Sascha Hilgenfeldt (a professor of mechanical engineering at the University of Illinois Urbana-Champaign), conducted a series of experiments that captured and manipulated the behavior of DNA molecules on particle surface surfaces.
This video shows how a blue particle initially bonds to three red particles at room temperature, satisfying its valence. These bonds break when the particle heats up, but the particle then finds three red partners upon cooling. This shows that the particle can choose how many bonds it makes. The result suggests that DNA bonds between particles can be reversed and rearranged on the particle surface in order to maximize valence. Credit: Angus McMullen/NYUs Department of Physics
They submerged tiny droplets in a liquid solution at a micron scale, with particles half the size of a speck. These droplets contained "DNA linkers", molecular tools that have "sticky ends". They allow researchers to mix and match to create the desired structures.
"The beauty of this process is that we can program the properties a particular material such as elastic or brittle or even self-healing power once broken, because the bonds can be made or broken reversibly," says Brujic. "Creators can choose to add five particles that stick only to one another, 10 that stick just to one, 20 that stick just to three, and 20 that stick just to four, or any combination of these. This would enable you to create materials with specific topologies and architectures.
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