Chemical weapon detectors inspired by butterfly wings

GE is taking inspiration from the nanostructure of butterfly wings to develop sensors for detecting chemical weapons and explosives.

The US government-funded project involving scientists from Exeter University aims to create a device that alerts users if low levels of specific gases are present.

Although it is being developed for the military, the sensor could also be used for monitoring power-plant emissions, water purification and food-safety testing, and breath analysis for disease detection.

The project will build on research published by GE scientists in 2007 that showed that condensed gases can change the way the structures of certain butterfly wings interfere with light and so change their colour.

GE now hopes to recreate similar structures and then treat them with chemical absorbers so they can nearly instantly show whether certain gases are present.

Dr Peter Vukusic of Exeter University is an expert in the ‘structural colour’ that appears in butterfly wings and will help GE to model how the structure reacts with different gases.

Insects such as the blue morpho butterfly appear colourful because of the tiny 3D structures on their surfaces, rather than pigmentation.

‘The presence of regular structure at the right length scale will manipulate how light flows through or is reflected from a material,’ said Vukusic. ‘The most brilliant colours in insects will be structural colours.

‘GE have shown the proof of principle; now the goal is to make synthetic replications of the butterfly wings and design them appropriately for maximum response. We’re also looking for similar structures that may be even more optimal.’

The team is looking at using lithographic-based techniques to build up simple organic structures and gradually optimise them. The structures will then be coated with chemicals that match the molecular shape of the gases in order to encourage them to attach to the sensors and allow the creation of different types of detectors.

GE’s principal investigator, Radislav Potyrailo, said: ‘GE’s bio-inspired sensing platform could dramatically increase sensitivity, speed and accuracy for detecting dangerous chemical threats.

‘All of these factors are critical − not only from the standpoint of preventing exposure, but in monitoring an effective medical response, if necessary, to deal with such threats.’

The four-year project is funded by a $6.3m (£4m) grant from the Defense Advanced Research Projects Agency (DARPA) and involves researchers from the University at Albany and the US Air Force Research Laboratory, as well as Exeter University.