Engineers from the Massachusetts Institute of Technology (MIT) published a research in the journal Nature Materials about the possibility of using spinach as biological bomb detectors.  They said it still needs to be tested for real, but it could eventually lead to a possible sowing of seeds across a site suspected of containing landmines and use the plant detection system to locate them.

The researchers said that by embedding tiny tubes in the plants' leaves, they can be made to pick up chemicals called nitro-aromatics, which are found in landmines and other buried munitions.  Information can then be relayed wirelessly real time through a handheld device.

Professor Michael Strano, co-author of the study, said, "our paper outlines how one could engineer plants like this to detect virtually anything. The plants could be used for defense applications, but also to monitor public spaces for terrorism related activities, since we show both water and airborne detection.  Such plants could be used to monitor groundwater seepage from buried munitions or waste that contains nitro-aromatics."

The researches implanted nanoparticles and tiny cylinders of carbon called nanotubes into the spinach plant's leaves.  They then used a laser to prompt the embedded nanotubes to emit near-infrared fluorescent light.  To detect this, they used an infrared camera connected to a Raspberry Pi computer.  The scientists can pick up signal from about 1m away from the plant and they are currently working on increasing that distance.

This is not the first time that plants have been tweaked using nanotechnology.  Strano's team used similar techniques to improve plants' photosynthesis ability and to develop detectors for hydrogen peroxide, TNT, and the nerve gas sarin.  "The goal of plant nanobionics is to introduce nanoparticles into the plant to give it non-native functions.  This is a novel demonstration of how we have overcome the plant/human communication barrier," Strano said.