All Venice Biennale 2025 there are not only art installations, but also three-meter-high living structures that literally breathe. They are made of 3D-printed cyanobacteria, capable of absorbing 18 kilograms of CO2 per year each.
The idea born in the laboratories of ETH Zurich transforms billion-year-old bacteria into microscopic workers that build and reinforce building materials. While traditional cement generates 8% of global carbon emissions, these biological bricks do the opposite: They eat carbon dioxide from the atmosphere and turn it into solid minerals. A paradigm shift that could change the way we build forever.
How Construction Cyanobacteria Work
Professor Mark Tibbitt and his team at ETH Zurich have solved a seemingly impossible problem: how to keep microorganisms alive inside a building material. Their solution is ingenious: cyanobacteria are stably incorporated into a printable gel which provides them with everything they need to survive and proliferate.
These ancient photosynthetic organisms are among the first inhabitants of the Earth, having appeared 3,5 billion years ago. Their special feature is the ability to capture CO2 through photosynthesis and transform it into biomass and, even more interestingly, into calcium carbonate: the same material that forms the basis of traditional cement.
The process requires only three basic ingredients: sunlight, artificial seawater with readily available nutrients, and carbon dioxide. The researchers optimized the geometry of the 3D printed structures to ensure optimal light penetration and passive nutrient flow through capillary forces.
The Double Carbon Capture That Changes Everything
What really makes this material special is its double carbon capture mechanism. As explained in the study published in Nature Communications, cyanobacteria not only store CO2 in organic biomass, but also trigger the precipitation of insoluble carbonates through a process called MICP (microbially induced carbonate precipitation).
Dahlia Dranseike, first author of the study together with Yifan Cui, explains that this double mechanism allows the material to sequester 2,2 milligrams of CO2 per gram of hydrogel in just 30 days, reaching 26 milligrams over 400 days. The most surprising fact? Longevity: encapsulated cyanobacteria They remain productive for over a year, continuing to harden the material from the inside.
From laboratories to the architectures of the future
The practical application of this technology is already a reality thanks to the work of the PhD student Andrea Shinling. For the Picoplanktonics installation in the Canada Pavilion at the Venice Biennale, the team scaled the process from laboratory format to architectural scale, building tree-trunk-like structures that capture CO2 like a twenty-year-old pine tree.
In parallel, at the 24th International Exhibition of the Milan Triennale, The installation “Dafne's Skin” explores how these living materials can transform building facades. On a structure covered with wooden shingles, microorganisms form a green patina that changes over time, transforming a sign of deterioration into an active design element that captures carbon.
Challenges for Cyanobacteria to Overcome
Of course, the road to commercial application still has hurdles. Cyanobacteria require controlled humidity to survive, which currently makes them unsuitable for the driest regions of the planet. The team is working to develop strains that are more resistant to dehydration.
Furthermore, industrial scalability requires significant investment and acceptance from a traditionally conservative construction industry. But the potential benefits are enormous: as highlighted in previous research, active biological materials could transform buildings from consumers of resources to producers of ecosystem services.
Tibbitt and his team see a future where these living materials can be used as facade cladding, turning every building into an active carbon capture system throughout its life cycle. No longer inert constructions, but architectural organisms that breathe, grow and actively contribute to the well-being of the urban environment.
