Researchers hope to increase the many functions of plants by enhancing them with nanomaterials; this could allow them be used for applications such as monitoring pollution.
The research team was able to increase the plants' ability to capture light by 30 percent "by embedding carbon nanotubes in the chloroplast, the plant organelle where photosynthesis takes place," a Massachusetts Institute of Technology news release reported. If other types of nanotubes were embedded the plants were able to detect atmospheric nitric oxide.
"Plants are very attractive as a technology platform," Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering and leader of the MIT research team, said in the news release. "They repair themselves, they're environmentally stable outside, they survive in harsh environments, and they provide their own power source and water distribution."
"The potential is really endless," he said.
Researchers made the discovery while attempting to isolate photosynthetic function in chloroplasts in an attempt to use them in solar cells. Chloroplasts aid in the process of photosynthesis; as electrons from absorbed light flow through the chloroplasts' thylakoid membranes creating energy that helps the plant build sugars.
Chloroplasts can still perform these functions when removed from the plant, but start to break down after a few hours from light and oxygen damage.
The team injected the Chloroplasts with cerium oxide nanoparticles (nonoceria), which helps with preservation. The team also embedded "carbon nanotubes, coated in negatively charged DNA," the news release reported. These nanotubes act as "artificial antennae" to help the plants capture additional ranges of light.
The team applied a solution of nanoparticles to the leaves of another plant, which penetrated tiny pores (stomata) which normally allow carbon dioxide to flow in and oxygen to flow out, this boosted electron flow by about 30 percent.
The researchers are not sure how the process affects sugar production.
"This is a question that we are still trying to answer in the lab: What is the impact of nanoparticles on the production of chemical fuels like glucose?" postdoc and plant biologist Juan Pablo Giraldo said in the news release.
The researchers were also able to use the nanotubes to detect gas nitric oxide, which is "an environmental pollutant produced by combustion," the news release reported.
"We could someday use these carbon nanotubes to make sensors that detect in real time, at the single-particle level, free radicals or signaling molecules that are at very low-concentration and difficult to detect," Giraldo said.
"This is a marvelous demonstration of how nanotechnology can be coupled with synthetic biology to modify and enhance the function of living organisms - in this case, plants," James Collins, a professor of biomedical engineering at Boston University who was not involved in the research, said in the news release. "The authors nicely show that self-assembling nanoparticles can be used to enhance the photosynthetic capacity of plants, as well as serve as plant-based biosensors and stress reducers."
