Engineers at the Massachusetts Institute of Technology (MIT) have succeeded in fitting spinach plants with sensors that are capable of sending emails when toxic pollutants accumulate inside plants. This is the latest development in the rapidly developing field of plant nanobionics, which is an experimental research that involves using electronic sensors on plants.
The plant has been programmed to send an email anytime it detects the presence of harmful compounds in the soil using a combination of carbon nanotubes and infrared cameras. The spinach roots have the ability to identify harmful substances in groundwater.
Although the engineers claim that such systems can be modified to alert us about risks related to pollution and climate change because plants are so sensitive to ecological changes, the experiment was designed to find explosives.
The discovery is a component of a 2016 study that was published in the journal Nature Materials, but it only recently gained attention after being included in a Euronews piece alongside a brand-new MIT study.
Nitroaromatic toxicants, which are present in industrial pollutants and explosives, frequently penetrate into the ground and get into plant tissues. These compounds build up in mesophylls, tissues found in the dense centre of leaves, during transpiration (the loss of water from leaves).
Researchers have also suggested that plant nanobionics might be used to monitor the environment because plants are quick to detect and respond to environmental changes.
By capturing energy from photosynthesis, researchers had previously ‘trained’ plants to shoot selfies using a similar approach. Photosynthesis is the process through which plants transform solar energy into glucose and oxygen.
The soil’s bacteria and microorganisms subsequently degrade this glucose, releasing more energy in the form of protons and electrons. Finally, this energy activates a camera, which “selfies” the plant.
The plant can theoretically act as a fuel cell thanks to this energy release, making it a more promising, clean source of energy, particularly for automobiles.
Spinach as fuel cells
Another MIT team’s more recent study discovered that spinach powder can be used as a source of carbon, iron, and nitrogen for making carbon nanosheets. The carbon nanosheet cells were discovered to be more effective because spinach contains significant levels of iron and nitrogen, which act as catalysts for oxygen reduction reactions that generate energy in fuel cells.
In comparison to conventional lithium-ion batteries, fuel cells, such as these metal-air batteries, are also more energy efficient. The use of spinach powder as a catalyst demonstrated both an increase in energy output and long-term stability. Methanol, a substance that has an impact on conventional cells, was also found to have no effect on the plants.
Social media users in the meantime came up with a number of amusing responses to the concept of spinach plants delivering emails.