Borrowing nature's brightest idea
Photosynthesis is the unique natural process that converts energy from sunlight into chemical energy. Understanding the photochemical reactions behind this essential phenomenon has the potential to deliver new sources of green energy as well as instruments that detect environmental pollution and food contamination.
“Photosynthesis is one of the most important biochemical processes,” explains Dr Giuseppina Rea of the Institute of Crystallography in Rome. It is responsible for most of the oxygen on our planet, also providing the food and the energy behind humans’ activities.
Scientists have been working to understand the complex fundamental science behind photosynthesis in the hope of capturing its secrets and mimicking it. Dr Rea led COST Action PHOTOTECH, which brought together an international research network of leading scientists and early-stage researchers involved in the development of photosynthesis-based devices.
Photo: PHOTOTECH group at the Action's final conference
The primary focus was on the development of biosensors that can detect pollutants – such as pesticides and heavy metals – which interfere with photosynthesis.
When these contaminants are present, the light-induced electron transfer is slowed down. This modification can be measured by photosynthesis-based biosensors. The network has designed two biosensors prototypes that sense changes in the photosynthesis process and could be used in industry.
In particular, researchers have shown that the photosynthetic complexes can be stably integrated with non-biological electronic components (bio-hybrids) enabling the measurement of light-induced photocurrents.
“The main achievement of our Action was the development of a class of bio-organic-inorganic hybrids to be used in devices for environmental monitoring and agrifood quality analysis,” says Dr Rea.
The network has generated novel bio-sensing elements for the detection of herbicides exploiting the power of molecular engineering to improve the performance of photosynthetic complexes. The scope of the Action broadened as the network learned more about the potential for using the developed photosynthetic biotechnology to produce green energy. “Newly developed bio-hybrids were stable and efficient enough and could be the basis for the development of clean energy devices,” says Dr Rea. “There is a big opportunity to use novel natural or bio-mimetic systems to produce electricity or hydrogen. This area is really exciting and has huge potential.”
The network has developed photosynthesis-based bio-photovoltaics and bio-photoelectrochemical cells that can harness energy from light.
Members are also working on the large-scale cultivation of microalgae, which may provide a cleaner, greener source of food, feed and bio-fuels. This will be the subject of a future COST Action. “This addresses what the bio-based economy is calling on researchers to deliver,” Dr Rea says. “It could have very important applications and is based on decades of fundamental photosynthesis research.”
During the four-year Action, the Action organised a range of networking activities, including 30 interactive short-term scientific missions, which helped to share knowledge among the research community. Based on these exchanges, 45 papers were produced, and several applications for national and international projects have been approved. Examples include "NANOBIO", a joint research project (2015-2017) between CNR-Italy and RFBR Russia. Given the pressing need for sustainable sources of energy and food, photosynthesis research could have a major social impact in the decades to come.