NTU researchers studying structure of mantis shrimp claw

Sharon See Channel NewsAsia 13 Jun 12;

SINGAPORE: The mantis shrimp may look like a lobster, but one weapon it has sets it apart from its cousins.

Its claw is capable of unleashing a force of more than 50 kilogrammes, which is a hundred times its own weight.

And researchers at the Nanyang Technological University are on their way to finding out the secret behind this weapon.

They have generally divided it into three components - a common bone material found in humans, calcium carbonate which is commonly found in shell fish and chitin, which is a natural polymer fibre that resembles cellulose in plants.

Assistant Professor Ali Miserez, who is from the School of Materials Science and Engineering at Nanyang Technological University, said: "There is a combination of factors but mostly, it's the fact that you have a building block which is arranged together in a very specific manner. If you take each individual building block, it is not that impressive actually. What makes it very unique is how the blocks, the minerals and the natural polymer are arranged together and form the entire structure."

This unique structure allows the mantis shrimp to smash its prey without damaging its own claw.

The next step is to better understand how the components can be put together so that the material can be replicated in the lab.

Asst Prof Miserez said: "We can use the exact same component... and try to reorganise it at the nanoscale. The other thing is we can actually use the concept and design that we see in the structure so that we can have different materials and try to arrange them in the same way that we see in these natural materials."

It may take five to 10 years before the structure of the mantis shrimp club can be replicated but Asst Prof Miserez believes there are many potential biomedical uses for such a tough material.

"If we can fully mimic this, we can make new implants that don't suffer wear and damage. For instance, an artificial hip will wear off over time. With this system, we could prevent abrasion. That will be a huge breakthrough because this is a big problem with biomedical and orthopaedic implants."

He added the material may potentially be used to make bullet-proof vests or even aircraft components.

- CNA/fa

Shrimp power to boost medical implants
Straits Times 15 Jun 12;

THE Mantis shrimp may weigh 400g on average but it can knock out prey with force and at great speed.

A research team's finding of why the creature's 'arms' can withstand impact and abrasion could now be applied to making medical implants that are lighter and up to 500 times stronger than existing models.

Assistant Professor Ali Miserez from Nanyang Technological University's (NTU) School of Materials Science and Engineering and its School of Biological Sciences, his PhD student Shahrouz Amini and Harvard University's Dr James Weaver collaborated on the study of the shrimps' dactyl clubs.

These 'arms' allow it to generate a force exceeding 500 newtons and strike prey in 2.7 milliseconds, 37 times faster than the blink of an eye.

The team discovered that each club comprises many alternating stiff and flexible layers in a spiral structure. This highly damage-resistant property could prove useful in medical products like hip and joint implants, where the wear and tear of metal components may cause complications.

The team will now focus on developing a new bio-compatible material which would reduce known risks associated with these implants, like bone loss and disability.

Said Prof Miserez: 'Using a nature-inspired blueprint to design biocompatible implants is actually a 'shrimple' solution.'

The new material is expected to be lighter and more impact-resistant than existing products.

It could also be used in military armour, vehicles and aircraft components.

Prof Miserez said: 'I want to inspire young people to take up science research, by giving them a chance to participate in cutting-edge research, just like how I was inspired by my professors when I was a student.'

SHERRI LEE