If spiders’ silk could be harnessed, Fritz Vollrath would be a very happy man. Vollrath, a professor of zoology at Oxford University in Cambridge, has spent 33 years studying spiders, their webs and their mysterious methods of web production.
He is also on the forefront of producing new web-based technology, and not of the URL variety.
In his lecture, “Silk: the Secret of a Spider’s Success,” Vollrath shared his research and knowledge with more than 150 ECU students and faculty April 29 as part of the Burroughs Wellcome Distinguished Lecture in Science.
Spider silk is one of the strongest and most flexible materials known to mankind – even stronger than Kevlar – and researchers like Vollrath have been researching how best to commercially synthesize it for years.
“Spider silk is tougher than Kevlar because it can absorb more energy before it breaks,” Vollrath said. “When stretched a lot, silk is work hardened by rearrangement of molecular chains. Kevlar does not stretch and therefore just breaks.”
The elasticity of spider webs is the result of beads that form on the web, enabling the silk to coil up, stretch to great lengths, and be restored to its original length, without breaking.
“With the webs of garden spiders, the function is the same as you find in an aircraft carrier, essentially,” Vollrath said. “The idea is to stop energy over a very short fall and you do it with straps. If you were to use a single strap, it would rip the tail out of the airplane, or the strap would break; you don’t want either. This is effectively what a spider web does on a micro-scale.”
Providing digitized diagrams of spiders producing webs, Vollrath showed that not all spiders create webs in the same way.
“Observing behavior gives you an idea about the structure of the web,” he said. “If you have a sense of structure you can go back to their behavior.”
While progress has been made in understanding the developmental pathways in the spider, Vollrath noted that how the spider produces its web remains a mystery. The kinds of silk spiders use, he said, are varied for different tasks. The dragline silk, from which a spider hangs, is not sticky and is believed to be the strongest form of silk. Silk used for trapping prey is much stickier, he said.
Vollrath is embarking on two new business ventures, Oxford Biomaterials and Spintec Engineering. The former deals with biomedical applications of spider silks and the latter with spinning artificial silks ‘the spider’s way’.
ECU biophysics professor John Kenney and ECU biologist Jason Bond worked together to bring Vollrath to campus through the Wellcome-Burroughs grant.
“Professor Vollrath’s work has invigorated my interest in spider silk as a wondrous material very much worth studying. Having such an eminent scholar visit ECU and present his work has given students and faculty at ECU a first-hand account of world-class research,” said Kenney, who is also an adjunct biology professor.
Kenney said he appreciated that Vollrath’s lecture encompassed a range of scientific disciplines, including biology, chemistry and physics.
“Research in spider silk involves biology (which organisms make such stuff and how did they evolve to do so); chemistry (what chemical and molecular controls are used to make such stuff); and physics (what are the material properties of this stuff and how do we measure them),” he said.