Faces of innovation: Nora Colson

"During future missions to the Moon or Mars, astronauts will need systems that continuously recycle essential resources. Cyanobacteria, microscopic organisms that use sunlight to grow, are interesting for this purpose because they absorb carbon dioxide and produce oxygen and biomass.

In my PhD, I investigated whether the space-relevant cyanobacterium Limnospira indica could take on an additional role: generating an electrical current when exposed to light. I tried to connect these living organisms to an electrode made from boron-doped diamond, an exceptionally stable material.

The main challenge was getting the biological and synthetic components to work together. The cyanobacteria did not naturally attach well to the diamond, so I developed a thin, mussel-inspired polydopamine layer that holds them close to the electrode while preserving their activity. This bio-hybrid electrode produced an enhanced light-dependent current. Although it is still an early-stage concept, it represents a first step towards living, light-driven technologies for regenerative systems in space."

"My PhD brought together materials science, biology, electrochemistry, photosynthesis research and space technology. It was conducted within IUMAT, in collaboration with SCK CEN and Empa (Switzerland). Each partner brought different expertise to the project, from diamond electrodes and material characterization to cyanobacteria, irradiation studies, and photoelectrochemistry. 

This collaboration taught me that a material cannot be judged by its individual properties alone. Boron-doped diamond is stable, conductive and chemically robust, but that did not automatically make it a suitable surface for living cyanobacteria. The decisive factor was the interface connecting both components. Even the shape of the cyanobacterial filaments affected the electrode’s performance.

I now see materials technology as the design of an entire system rather than the selection of one material. Some of the most interesting discoveries emerge when people from different disciplines and institutions examine the same problem from different perspectives."

"My EUREKA moment began with a conversation at a summer school organized by the European Society for Photobiology. I was looking for a way to attach cyanobacteria firmly to a diamond electrode without harming the cells or preventing electron transfer. Massimo Trotta, from CNR Bari, suggested that I investigate polydopamine, a mussel-inspired material known for adhering to many different surfaces.

That suggestion became a turning point in my PhD. Polydopamine formed a thin, biocompatible layer that anchored the cyanobacteria to the diamond while preserving their photoelectrochemical activity. Seeing that this approach not only worked but also enhanced the generated photocurrent was the real EUREKA moment. It demonstrated how one conversation outside your immediate field can redirect an entire research project and lead to its central result."