Spider's silk to be used for nanomotors

Indian scientists have found a novel way to use spider’s silk as a new material to manufacture gen-next ultra-small products, ranging from nanomotors for robots to silk-based sensors that can be used to design futuristic spacecraft.

Spider’s silk, when processed, can also be used to create materials to weld damaged tissues or organs in the body, thereby doing away with suturing.

Other potential applications range from developing micron-sized cantilevers to tiny Mobius Strips (a surface with only one side) that can be used to generate mechanical forces from light.

The technology created by a trio at the Indian Institute of Science, Education and Research (IISER), Mohali, relies on the use of fleeting laser pulses to micro-weld silk with materials such as metal, glass and Kevlar with strengths comparable to pristine silk.

The outcome is a range of wonder materials that could be exploited for diverse futuristic applications.

In a spider’s web, there are two types of silk. The spider uses a particular type of silk to build its complex web.

There is a second type of silk that the spider exploits at the centre of the web to trap the insects. This is highly elastic and five times stronger than steel.

It is the second type of silk that was used by the IISER team for the experiment. Though some of the excellent properties of spider’s silk are well known, there is barely any technology available to process the silk and weld it with other materials.

In search of an effective process technology, physicist Kamal P Singh and his students Mehra S Sidhu and Bhupesh Kumar decided to shine femto-second laser pulses on the silk.

With too much energy, the silk was getting damaged, while at low energy there were no changes. But at an optimal energy level, the IISER team found that the silk was getting bulged when hit by the laser without any property loss.

It opened up a new window of opportunity to the team to weld spider’s silk with other materials.

“Manipulating spider’s silk on a nanometre scale was difficult because the silk couldn’t be cut without destruction. Ours is a minimally invasive procedure to bend, mould and weld the spider’s silk in which the structure of the silk remains intact,” Singh told DH.

Details of the IISER technology were published in a recent issue of the journal 

Nature Materials

. Because of its commercial potential, the team also filed a patent application on the technology.