Research conducted by the Massachusetts Institute of Technology (MIT) Plant Nanoelectronics team includes luminescent plants that have been planted to emit faint light for about 4 hours. The researchers embedded special nanoparticles into the watercress plants to make the plants glow. Recently, the team showed their research in Bangkok, Thailand.
Project engineer Michael Strano said that their vision is to allow plants to work like a desk lamp so that a lamp does not need to be plugged into a power outlet, but instead provides electricity through the plant's own energy metabolism.
Principle of illumination
To create a glowing plant, the MIT team used luciferase, an enzyme that sparkles fireflies. Luciferase acts on a molecule called luciferin that causes it to glow. Another molecule, called coenzyme A, is useful for removing processes that inhibit luciferase reaction by-products.
The research team placed the three components in separate nanoparticle carriers. Nanoparticles are all made by materials that the US Food and Drug Administration categorizes as "usually considered safe." These nanoparticles help each ingredient reach the proper part of the plant and also prevent the ingredient from reaching concentrations that may be toxic to the plant.
The researchers used SiON nanoparticles with a diameter of 10 nm to carry luciferase, and additionally used larger PLGA polymer particles and chitosan to carry luciferin and coenzyme A, respectively. In order to allow the particles to enter the leaves of the plant, the researchers first suspended the particles in solution, then allowed the plants to immerse into the solution, and then subjected to high pressure treatment, so that the particles passed through the small holes, also called "pores", into the leaves.
The particles releasing fluorescein and coenzyme A accumulate in the extracellular space of the mesophyll, the inner layer of the leaves. The smaller particles carry luciferase into the cells that make up the mesophyll. The PLGA particles gradually release fluorescein, which then enters the plant cells, where the luciferase chemically reacts to fluorescein.
At the beginning of the project, the researchers' early work focused on producing plants that could shine for 45 minutes. Now they have raised this time to 3.5 hours, which is about 6% of the brightness of LED lights.
The light produced by a 10 cm seedling seedling is currently only one thousandth of the amount of light required for reading. However, the researchers believe that by further optimizing the concentration and release rate of the ingredients, they can enhance the illuminating effect and durability.
In addition, the researchers showed that they turned off the light by adding nanoparticles carrying a luciferase inhibitor. This allows the plants they eventually develop to stop illuminating depending on environmental conditions, such as daylight.
Previously, the work of creating luminescent plants relied mainly on genetically engineered plants to express the luciferase gene, but this was a laborious process and the light produced was extremely weak. These studies are primarily aimed at tobacco plants and Arabidopsis, and are commonly used in plant genetic research. However, the method developed by Strano's laboratory can be applied to any plant. Currently, in addition to watercress, they also showcase this technology through arugula, kale, and spinach.
According to researchers, the technology is also used for low-intensity indoor lighting or to turn trees into self-powered street lights.
According to Strano, their goal is to treat plants as they are seedlings or mature, and to continue to function during the plant's life cycle. Through careful and careful research, in the future they will open up a way for the trees to be directly used for home lighting after being processed.
Currently, the technology is coming to the ground.
Cooperation with Thai real estate developers
Strano presented his research in Bangkok on Monday as part of a partnership between MIT and Magnolia Quality Development Corporation Limited (MQDC), Thailand's premier real estate developer with a research and development center, RISC, to reduce Thailand. Greenhouse gas emissions from real estate development.
After he succeeded in producing a prototype of a table lamp that relied on the growth of the bean sprouts, the professor and the center will jointly research and develop trees that can operate as self-contained circuit lights.
Strano proposed four trees for this experiment - teak hardwood, mango plum, Burmese grape and dipterocarpaceae. They will study which leaves are most suitable because different leaves have different qualities. Some leaves are waxy and some have a more permeable surface.
They hope to develop trees that can shine, as street lights for Forestias. Located on 119 acres in Bangna, a suburb of Bangkok, Forestias was developed by MQDC and is a mixed-use project that promotes the concept of “imagining happiness” and integrates natural ecosystems into the community.
Strano's ultimate goal is to develop trees that can illuminate and act as street lights in new projects, which are scheduled to open in five years.
In the future, researchers hope to develop a method of painting or spraying nanoparticles onto plant leaves based on this technology, which can transform trees and other large plants into light sources.
Strano plans to return to Bangkok in November, when he hopes to bring prototypes of second-generation technology and showcase results in RISC labs. He said that if the research achieved such results, the trees that could shine would be more economical because it had no energy costs and did not need to be connected to the power system.
Singh Intrachooto, Principal Consultant at RISC, said that Strano's work opens up exciting possibilities for further integrating natural ecosystems into residential communities. He added that lighting accounts for about 20% of global energy consumption, so glowing trees can bring huge environmental benefits.
