Natural silk like that produced by spiders and silkworms could be a cheap, sustainable, and environmentally friendly alternative to glass, plastic and traditional materials used in manufacturing.
Two research teams—hailing from the United States and France—exploring the properties of silk and its particular application in the medical field will present their latest findings this week at the Frontiers in Optics 2012 conference in Rochester, N.Y.
The U.S. team from Tufts University in Boston has been busy fabricating silk proteins for implantable sensors and other technologies, while the French team from CNRS Institut de Physiques de Rennes is using natural spider silk to guide light through photonic chips, which could eventually lead to silk-based biosensors and medical imaging devices for use inside the body.
Silk is one of the strongest natural materials, stronger than steel when compared pound for pound. Made of water and protein and processed at room temperature it’s also eco-friendly and biodegradable. It can be implanted in the human body without causing any immune response and can function as part of a living system.
The Tufts team has developed silk-based materials that look like plastic, but retain the properties of silk. The hope is that within the next ten years doctors might be able to implant a sensor made of silk protein at the site of a fractured bone to monitor healing, and then have the sensor dissolve after it’s served its purpose.
The team, led by Fiorenzo Omenetto, manufactures its own silk by pouring a water and protein solution and letting it set into a film.
Omenetto believes that silk can have many practical applications in the medical field, from micro needles to human veins. And because silk acts like a cocoon around biological matter, it’s possible to add antibodies or medicine to liquid silk. An implanted silk device for instance could deliver drugs to heal the body after surgery.
Silk is also an excellent conductor of light, working in a similar way to glass microfibers used to carry light within a chip. But while glass microfibers have to be heated to high levels and carefully sculpted at great expense, silk is readily available and cheap.
The Tufts team has already developed and tested a blue laser which utilizes silk rather than the incredibly expensive sapphire and gallium nitride surfaces used in most blue lasers today.
The French team is using real spider silk to experiment with taking pictures inside the body. Natural silk is less than a tenth the width of a human hair and could carry light into the body through a very small opening, providing a less invasive way to do internal body imaging on patients.
And the potential uses for silk are not just confined to the medical field. Silk is completely biodegradable making it perfect for water bottles, cups and food packaging too, and it’s edible which means that in the future we may be seeing the ultimate in sustainability – “smart packaging” around food which, instead of unwrapping and throwing away, we’ll be eating.