Spider Silk... A new dimension in Silk Technology and Textile... |Bappi

Friday, December 6, 2013

Spider Silk... A new dimension in Silk Technology and Textile...

Spider silkis aproteinfiberspun byspiders. Spiders use theirsilkto makewebsor other structures, which function as nets to catch other animals, or as nests or cocoons for protection for their offspring. They can also suspend themselves using their silk.

Many small spiders use silk threads forballooning, the popular, though technically inaccurate, scientific term for the dynamic kiting spiderlings (mostly) use for dispersal.

They extrude several threads into the air and let themselves be carried away by winds. Although most rides will end a few yards later, it seems to be a common way for spiders to invade islands. Many sailors have reported that spiders have been caught in their ship's sails, even when far from land. The extremely fine silk used by spiders for ballooning is known asgossamer.
In some cases, spiders may even use silk as a source of food.
Methods have been developed to silk a Spider forcibly.
Uses:
All spiders produce silks, and a single Spider can produce up to seven different types of silk for different uses.This is in contrast to insect silks, where most often only one type of silk is produced by an individual.Over the 400 million years of evolution, spider silks may be used for a number of different ecological uses, each with properties to match the function of the silk (see Properties section). The evolution of spiders has led to morecomplex and diverse uses of silk throughout its evolution, for example from primitive tube webs 300–400 mya to complex orb webs 110 mya

Silkworms have been genetically engineered to spin spider silk.
The new hybrid silk is finer and tougher than ordinary silk.
The development could lead to wound-healing, lighter body armor as well as artificial tissue.
If Spider-Man ever ran out of webs, he could now enlist an army of silkworms to spin extra high-tensile spider silk.
Scientists have created a genetically modified silkworm that spins a new kind of silk: a hybrid of silkworm silkand spider silk.
The new material alone could shake up the textile industry, while future silk hybrids could be used in everything from bulletproof clothingto artificial tendons.
"Compared to normal spider silk, it's not as strong," said Malcolm Fraser, a scientist from the University of Notre Dame. "But we are confident that, this being our first attempt, that we will be able to tweak the system to bring the system closer tothe strength of true spider silk."
Fraser, along with professor Randy Lewis from the University of Wyoming, developed the spider-silk-spinning silkworms.
Silkworms have helped clothe people for thousands of years by reliably producing large quantities of a soft, supple and luxurious material.
Spider dragline silk is significantly stronger than silkworm silk -- so strong that it can best steel wire -- but it is hard to make.
"They just don't produce enough silk," said Fraser, who notes that a golden cloth on display at the American Museum of Natural Historyin New York City required more thanone million spiders to produce. "Onemillion silkworms can produce considerably more silk than one million spiders."
The new silk is a hybrid of spider silkand silkworm silk. It is stronger and finer than silkworm silk, but not quite as strong as spider silk. "It would definitely be stronger (than a normal silk shirt)," said Lewis. "But itwouldn't flow like silkworm silk does."
"It's a fabulous accomplishment," said Cheryl Hayashi, a spider silk expert and a professor at the University of California, Riverside.
Other groups have produced spider silk protein in plants, in bacteria andeven in goat's milk. But spider silk protein is not the same as spun spider silk. The silkworms have the necessary body parts to spin the protein into silk threads -- and to produce it in large quantities.
The new silk alone could shake up the textile industry by creating a softer, stronger fabric that still looks like silk.

Fraser and his team, however, have bigger plans in mind.
In this work the Notre Dame and University of Wyoming scientists replaced only one of multiple silk-producing genes in silkworms with spider silk genes. Eventually they want to replace multiple silkworm silk-producing genes with spider silk genes.
In particular, they hope to insert genes from the newly discovered Darwin's Bark Spider ( Caerostris darwini ), which produced silk twice as strong as any other. That's more than 10 times stronger than Kevlar, a fabric commonly found in bulletproof vests.
Mass produced, stronger-than-steel spider silk will also have a range of biomedical applications, said Fraser and Lewis. Hybrid silk could be speed wound-healing, eliminate or reduce the need for cadaver-derivedtendons and ligaments.