It’s hard to explain what Prof. Ehud Gazit and his colleagues at Tel Aviv University find so exciting. Even Gazit, someone who has been working in organic nanotechnology for years, says he’s still taking his first steps in a boundless new realm in which biology and nanotechnology combine.
- Nanotech Answer to Personalized Cancer Therapy
- Israeli Scientist Bends the Rules
- Using Gold to Detect Tumors
- The Best Haaretz Science Stories in 2014
After the polymer revolution of the 20th century that gave us plastics, PVC and silicon, Gazit calls the combination of nanotechnology and biology the materials revolution of the 21st century.
So it seems possible that in a few years we’ll be using flexible computer or television screens based on proteins and DNA particles, without metals or copper wires. And anyone who’s worried about artificial intelligence leaving mankind behind can add a biological dimension: These proteins and DNA particles combine by themselves.
In October, three Japanese scientists won the 2014 Nobel Prize for Physics. Their invention is appreciated in nearly every home and street in the Western world: The diodes that emit blue light enable the mass production of economical LED lights.
But the world of optics and artificial lighting aspires to more. It wants to become more efficient, more energy-saving and less damaging to the environment.
In recent years OLED technology, which builds screens made out of organic materials, has been taking its first steps. But according to an article this month in Nature Nanotechnology, Israeli researchers have developed nanostructures based on biological materials that emit light in response to voltage.
Greener and less expensive
The people at Nature Nanotechnology were impressed because for the first time nanotechnology has seen the combination of protein and DNA in optics.
“Our laboratory specializes in producing biological nanotechnology; that is, nanometric structures made up of organic materials,” Gazit says. “This is both greener and less expensive; it also enables the creation of new technologies that can’t be produced by inorganic materials like semiconducting metals.”
Nanobiotechnology (or bionanotechnology, depending on whom you ask) is in the forefront of nanotechnology research. The research employs two of the most basic building blocks in nature: DNA strings and peptides – the building blocks of proteins. The scientists have created a new material: very tiny particles based on a combination of peptides and DNA.
“We arrived at this almost by chance,” says doctoral student Or Berger, who did his research under Gazit. “For many years our laboratory has been working on the nanotechnology of peptides – short strings of amino acids — and when I started working on my doctorate I wanted to combine this with the nanotechnology of DNA. But the optical properties of these particles was discovered by chance.”
“We aren’t the first to develop peptide-like DNA,” adds Gazit, “but we’re the first in the world to employ this material in nanotechnology .... We have here a very strong special architecture, but we asked ourselves what could be special about these structures even beyond their unique molecular architecture.”
The researchers found the answer when they inserted fluorescent dye, which makes parts of DNA light up, into the particles. They found that particles that hadn’t been dyed lit up on their own.
But there was another surprising discovery: From these structures, it was possible to produce any color in the range of visible light, unlike other fluorescent materials that make only one color possible. Thus was born the project that lasted two years.
“The structures were discovered to have unique optical properties,” says Berger. “Not only can they light up on their own, you can also get electroluminescence from them. That is, when voltage is applied to them, they emit light in a way similar to a LED bulb. So here there’s already a wealth of possible applications, like computer, television and smartphone screens.”
Significant savings, too
Berger notes that LED screens are made up of a number of layers of different materials, each of which can emit light of a specific color, thereby producing color screens. Because the new structures can emit light of any color, there are significant savings. Also, since these structures are based on biological materials, they’re much more environment-friendly than the materials currently in use, which contain heavy metals and other pollutants.
The discovery hasn’t only excited scientists. It has been registered as a patent by Ramot, the technology transfer company of Tel Aviv University, and it has won a grant from the university’s Momentum foundation. It’s now in the initial development phases.
“There is movement today toward electronics not based on metals – materials unfriendly to the environment — but rather on organic materials. One of the problems today in optics is obtaining light in the blue range of the electromagnetic spectrum,” Gazit says.
“We discovered that the structures that we produced provide good lighting in this range as well. We’ve created structures that build themselves, and we discovered that it’s possible to plan all kinds of matter based on self-construction. This is the start of a revolution based on nanotechnology.”
Gazit says he and his colleagues learned from biology how materials create very small nanometric structures; now they’re studying the wide range of physical properties.
“We’re talking about the emission of light that could be very effective for screens and electronics based on flexible platforms without metals. But this also comes with a vast potential of other properties like high mechanical strength and semiconductivity,” Gazit says. He calls this a new world of applications.
“We want to combine the two worlds: materials that on the one hand build themselves and can create orderly structures and on the other can be organized and controlled,” Gazit says.
“The great challenge in electronics is not miniaturization but rather the creation of mechanisms that build themselves based on the understanding that biology is a kind of machine — and to combine it with nanotechnology. The idea is to instill the properties you get in nanotechnology into larger and more specific mechanisms and let them organize themselves on their own.”