This website uses cookies primarily for visitor analytics. Certain pages will ask you to fill in contact details to receive additional information. On these pages you have the option of having the site log your details for future visits. Indicating you want the site to remember your details will place a cookie on your device. To view our full cookie policy, please click here. You can also view it at any time by going to our Contact Us page.

Scientists' 'genetic switch' is able to detect TNT

05 July 2015

Cleaning-up post-war explosive chemicals could get cheaper and easier, using a new genetic ‘switch’ device, being developed by scientists at the University of Exeter.

Image: Shutterstock

“It's a bit like making mushroom soup made from dehydrated ingredients”, says the University of Exeter's Professor John Love, who is leading the research. "We take all the ingredients needed for gene activity, mix them together and transfer them onto paper to make a dipstick. When the mixture comes into contact with a contaminated water sample, it turns the genetic switch on which signals the presence of the pollutant.”

When TNT is present, transcription, which is the first step of gene expression (in which a particular segment of DNA is copied into RNA) goes ahead, and the promoter is turned on.

In contrast to previous detection systems that rely on biological components, this is a cheaper cell-free system with a longer shelf life, which needs very little expertise to operate it. The method is also specific for each chemical, which means that the clean-up can be targeted. 
Further research is needed before the system is ready for deployment. 

"We are tinkering with the switches that turn genes on, because we want the detector to be sensitive to different levels of TNT," says Professor Love. This will allow the detector to measure the concentration of pollutants as well as their presence. 

The original idea for the project came from a student competition called iGEM. As part of this competition, undergraduate students developed a biosensor integrated into a bacterium (E. coli) that would detect TNT in the environment.

The team at Exeter is hoping to develop the system further so that it will be able to detect not just TNT, but other contaminants too. 

The work was presented by Dr Charlotte Cook from Biosciences, University of Exeter, at the annual meeting of the Society for Experimental Biology (SEB) in Prague on Thursday 2nd July 2015.

Print this page | E-mail this page

Coda Systems