Boffins develop biosensor to sniff out explosives

Temple University School of Medicine researchers have developed a new biosensor that sniffs out explosives and could one day be used to detect landmines and deadly agents, such as sarin gas.

Washington, May 9 : Temple University School of Medicine researchers have developed a new biosensor that sniffs out explosives and could one day be used to detect landmines and deadly agents, such as sarin gas.

Biosensors are made from natural ingredients and are preferable to man-made sensors, which are expensive, cumbersome and inflexible.

To create the biosensor, Danny Dhanasekaran and his colleagues genetically engineered a yeast strain with mammalian (rat) olfactory signalling machinery, genetically linking it to the expression of green fluorescent protein.

Into these yeast cells, the researchers cloned individual rat olfactory receptors. When these olfactory receptors "smell" the odour of DNT, an ingredient in the explosive TNT, the biosensor turns fluorescent green.

According to Dhanasekaran, Associate Professor of Biochemistry at Temple's Fels Institute for Cancer Research and Molecular Biology, their team is the first to identify, clone and sequence this novel olfactory receptor.

"We suspected that harnessing the potential of the olfactory system, which can detect innumerable chemical agents with unparalleled sensitivity and selectivity, would be of immense value in the detection of environmental toxins and chemical warfare agents even at sublethal levels," said Dhanasekaran.

The research team is now trying to perfect the utility of the biosensor and believes its potential applications could be exploited in the field of healthcare and medical technology.

The team expects the biosensor to be soon incorporated into a handheld device or a remote device that can be left at a location and monitored from afar.

"With further genetic fine-tuning of the olfactory receptor pathway, this system could also be used to screen experimental medications, a crucial step in the development of new drugs," said Dhanasekaran.

The findings are scheduled to appear in the June issue of Nature.

ANI