What is five times stronger than steel, yet as elastic as nylon?
The answer may surprise you.
It’s spider silk.
On July 15, the natural materials division of the Air Force Office of Scientific Research presented a three-year $420,000 grant to ASU to study this super-material.
“The final goal is to help understand the silk, so people can artificially produce it,” said Xiangyan Shi, a first-year graduate student in chemistry and biochemistry who helps with the research.
Scientists are able to artificially produce the proteins in spider silk, as well as the silk itself. However, the silk they create has none of the properties of real spider silk — super-strength or elasticity, said Gregory Holland, an assistant research professor in ASU’s Department of Chemistry and Biochemistry.
Spiders produce their silk in a unique way, said Jeff Yarger, an ASU professor of chemistry, biochemistry and physics. They store the solution of proteins, water and salt in glands and then, at will, they can create up to six unique kinds of spider silk.
The silks they create are insoluble, which means the spiders turn the solution into a fiber that cannot be dissolved in the solution from whence it came, Holland said.
The process that spiders go through at a molecular level to produce silk from a solution is what ASU researchers are focusing on. The hope is that, with this research, scientists will be able to artificially produce spider silk, Holland said.
Synthetically produced spider silk has a wide array of applications, which makes it valuable to many different fields, Holland said. It can be used for everything from super-light bulletproof vests and stronger parachutes, to replacement ligaments or tendons and super-strong cables.
“The applications are pretty much endless … anytime you want a super strong fabric, you could use spider silk,” Holland said. Along with Yarger, Holland is the principal investigator of the project.
The Air Force of Scientific Research isn’t the only organization interested in funding the research. ASU has also received a grant to study spider silk from the National Science Foundation.
Research with the current team started in 2006, Holland said. In August 2008, the NSF gave a $375,000 grant for the research, and in July 2010 the AFOSR granted $420,000 to ASU.
“This is a very exciting research project that touches all aspects of science,” Holland said.
The research primarily involves using Nuclear Magnetic Resonance Spectroscopy to view living spiders at an extremely small scale, Yarger said.
The NMR is used to look at the three-dimensional shape of the amino acids in each spider silk, Holland said. The way the proteins fold into shapes determines the properties of the silk.
Each silk has very distinct characteristics. “Drag line” silk, the silk most worked with, is five times stronger than steel, while other silks are extremely elastic or sticky, Yarger said.
According to Holland, it will take 10 to 20 years before researchers know enough about how spider silk is created to synthetically manufacture it, which is fairly typical for this kind of research.
However, Holland said, researchers should be able to understand “drag line” silk in about five years.
Reach the reporter at connor.radnovich@asu.edu
