In this world of the occasionally mad scientist, the latest announced innovation is quite an eye-opener. I mean, what could possibly be the connection between Goats Milk and Spider silk?
Developed first in China, silk has long been used to create expensive clothing, parachute material and even medical sutures, having been harvested from silk-worms, spiders etc., and is now the subject of intensive research.
Massachusetts Institute of Technology's Center for Materials Science and Engineering researchers found that, pound-for-pound, silk is stronger than steel, because the beta-sheet crystals within it - nano-sized cross-linking domains holding the material together – behave differently
The team used computer models, simulating exactly how these interact with one other, finding that hydrogen bonds unusually arranged play an important role in giving silk that incredible tensile strength. Among the weakest chemical bonds normally, in such close proximity, these bonds work together, becoming very strong.
Apart from that, should a single bond break, the many remaining contribute to the overall strength, because these beta-sheet crystals are able to self-heal, so that strength and ability of the silk, to bend or stretch without breaking, is down solely to those unusual atomic bond arrangements
Spider silk fibers are stronger than almost any manmade fiber and very elastic, the reason that folklore dating to the first century A.D. tells of webs being used as wound dressings. Modern medical research is looking at the material for possibly creating artificial ligaments and tendons, bulletproof vests and even car airbags, but quantity has always been a problem.
Spider farms simply never work, because arachnids are solitary, and tend to kill each other off over territorial disputes, and the limited numbers of spiders one can get in a defined are is just too small, but a solution may be at hand, in the shape of goats.
The National Science Foundation assisted the team in isolating the genes responsible for the silk-production in spiders, so that they can create transgenic goats, which produce the spider silk proteins in their milk. This means that when the goats in question lactate, the milk can be collected and the silk protein purified out in much higher amounts than has ever been possible before.
Of the seven kids born to the goats originally implanted, only three have the silk gene, but the numbers will increase as breeding continues, since the goats affected seem normal in every way other than the milk they produce.
Obviously, there need to be other ways, besides this one, to try creating the spider silk, and introducing the relevant genes into alfalfa plants has also been suggested, because alfalfa has high protein content, of around 25% making it an ideal crop for this use, what remains after the silk extraction used to make ethanol, or bio-fuel.
Spider silk could be employed for eye and other facial injuries, even jaw repair perhaps, normally difficult to treat because the repair material must be strong enough to allow jaw use during healing, which could happen with spider silk constructions. The reality is that this incredible material may not be available widely for at least another decade, but at least it is on the way.