Nanobionics led to super-powered plants after researchers were able to boost the photosynthesizing capabilities of plants by inserting carbon nanotubes into the cells of the leaves that create energy from light. In another experiment, the nanotubes were made to fluoresce in the presence of nitric oxide, turning leaves a glowing orange when the toxin was in the air. It is believed that these experiments will result in plants that can do more with less, leading to the ability to grow crops in harsher conditions and increase yields in plants grown for energy such as algae.
The hardest part of making the experiment work was getting the nanotubes into the chloroplast of the plants cells, which is the organelle directly responsible for the chemical reaction that allows plants to harvest energy from sunlight. Their first idea of watering plants with a solution of the nanotubes was unsuccessful, as the roots are structured in such a way as to prevent the nanotubes from being absorbed. The problem was solved by turning to the leaves, specifically the stomata, which are small pores on the underside of leaves that allow carbon dioxide in and water vapour and oxygen out. A syringe containing a pressurized nanotube solution was used to successfully introduce the additive to the interior of the plants leaves.
Once inside the leaf, researchers were able to get the tubes into individual cells by way of a polymer wrapped around them. The polymer sticks to the lipid bubble that surrounds the chloroplast and allows the nanotube to enter without tearing the membrane or leaving a hole. Once they knew how to get the pieces in place, researchers conducted the first experiment in nanobionics which led to super-powered plants.
By introducing nanotubes capable of absorbing a wider range of light wavelengths than plants, the researchers were able to increase the plants photosynthetic efficiency by 30%. The idea behind this is based on the knowledge that plants absorb only a small fraction of light from the overall spectrum, and the increase in efficiency was accomplished by allowing the plant to utilize light outside of its usual range of 400 to 700 nanometers.
The real beauty of plant nanobionics is that once the carbon nanotubes are in place, the array that allows plants to display non-native abilities is self-assembling. This is due to the nanotubes residing inside individual cells and working to enhance their function within the structure the plant already takes on naturally. In this meeting of chemical engineering, biology, and nanotechnology, the application of nanobionics leads to super-plants that may one day change the way we generate electricity, search for toxic hazards in the environment, or even where and how we grow our food. There are roughly 560 billion tons of plant biomass on Earth that is already responsible for keeping the air we breathe up to snuff. But with pollution and loss of forests ever on the rise, it may be that plant nanobionics is the helping hand they need to stay green.
By Daniel O’Brien