Nanotechnology has proven many times that it can be reliable and that it has enormous implications in many domains, however, researchers are looking to exploit all of its capabilities and to reach its full potential. On the other hand, researchers are also studying the human DNA to better understand the human body among others. Well, what if they could combine the two in order to get a revolutionary technique? A team of researchers at the U.S. Department of Energy from the Brookhaven National Laboratory have used DNA’s molecular assembly line to link up nanoparticles for high precision nanoconstruction.
This technique will help scientists to develop bio-sensors or better solar cells, as the DNA-like nanofabrication will probably get the best out of nanotechnology. In order to test this technique, the BNL researchers have used DNA to correlate nanoparticles in many shapes, even in 3D nanocrystals. According to the research team, the technique consists of coating the nanoparticles with strands of DNA as the segments of genetic code lead the nanoparticles to find each other, link up, and stick together in specific ways.
As the researchers were going further with their study, they used DNA-linkers to maneuver the nanoparticles and to attach them on a solid surface. Their goal was to control how the DNA-coated nanoparticles form. Although they feared that they can’t control the way nanoparticles link up, they noticed that it can be done with high precision and that the nanoconstruction technique is very predictable therefore they managed to build clusters from the nanoparticles. Please be aware that the DNA linkers were artificially built in the lab, and they “don’t code for any proteins as genes do.”
“When a particle is attached to a support surface, it cannot react with other molecules or particles in the same way as a free-floating particle,” said Oleg Gang, physicist at the Brookhaven National Laboratory, and leader of the research.
Gang says that “by controlling the number of DNA linkers and their length, we can regulate interparticle distances and a cluster’s architecture” which means that the researchers can rearrange and to create a desired construction. “Together with the high specificity of DNA interactions, this surface-anchored technique permits precise assembly of nano-objects into more complex structures,” he continued.
Also, the researchers can control and assemble the nanoparticles in very small structures. According to the researchers, they can assemble structures much smaller than 3D nanocrystals; they can put together the so-called “dimers” which are molecules consisting of two identical simpler molecules.
“When we arrange a few nanoparticles in a particular structure, new properties can emerge. Nanoparticles in this case are analogous to atoms, which, when connected in a molecule, often exhibit properties not found in the individual atoms. Our approach allows for rational and efficient assembly of nano-‘molecules.’ The properties of these new materials may be advantageous for many potential applications,” said Gang.
Aforementioned, I said that this DNA-based assembly technique for nanoparticles can lead to better solar cells. But how can it help? According to the researchers, when the nanoparticles are linked as dimers, an optical effect called plasmon resonance occurs. The plasmon resonance is a phenomenon which appears when metallic particles interact with an electromagnetic field, and as a result, it leads to a “collective oscillation” of the conductive electrons of the material. This means that engineers could eventually use the technology so that solar cells would absorb energy from the entire spectrum of light.
“The size and distance between the linked particles affect the plasmonic behavior,” explained Gang.
The study is only at the beginning and for now, the BNL researchers have applied for a patent, and they are looking to improve the technique and to see if the nanofabrication is scalable for high-throughput production. The researchers will learn more about the technique and we’re waiting to see what’s the best use for it. In the meantime, you can also check the video above and watch Gang explaining the method.