Engineers from the Massachusetts Institute of Technology (MIT) have successfully embedded electronic systems into spinach plants, making it work as a sensor that can detect explosives and wirelessly relay the information to a handheld device similar to smartphones.
Their new natural bomb-sniffing device, described in a paper published in the journal Nature Materials, is one of the first demonstrations of engineering electronic system into plants, or what the researchers call "plant nanobionics."
"The goal of plant nanobionics is to introduce nanoparticles into the plant to give it non-native functions," explained Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering at MIT and leader of the research team, in a press release. "This is a novel demonstration of how we have overcome the plant/human communication barrier."
In order to give spinach its bomb-detecting abilities, the researchers embedded carbon nanotubes into its leaves. These carbon nanotubes can be used as sensors to detect wide range of molecules, including hydrogen peroxide, the explosive TNT and the nerve gas sarin. The researchers engineered this carbon molecules into the leaves fo the plant using a technique called vascular infusion. The researchers first applied a solution of nanoparticles to the underside of the leaf, then placed the sensors into a leaf layer known as the mesphyll, where most photosynthesis takes place.
The plant is designed to detect chemical compounds called nitroaromatics. These chemical compounds are often used in landmines and other explosives. When one o these chemical compounds are present in the groundwater being absorbed and sampled naturally by the plant, the embedded carbon nanotubes will emit a fluorescent signal that can be read with an infrared camera that can be attached to a small computer similar to smartphone. The computer will then send an e-mail to the user.
This is not the first time that the engineers from MIT used spinach plant as sensors. They also engineered spinach plants to detect dopamine. The researchers also noted that plant nanobionics is not limited to spinach plants. Plants are the nature's very own analytical chemists, with the ability to detect small changes in the properties of soil and water potential.