Living Circular Labels (LCLs)

Flavobacteria are marine organisms that produce vivid, angle-dependent colour as their cells organise into
structures that interact with light. These optical structures, resulting in structural colour, are influenced by
environmental factors such as temperature and humidity. In this project, a collaboration was established
between Avans, Hoekmine and Bio4Life to develop Living Circular Labels that communicate environmental
signals through changes in the structural colour of the embedded Flavobacteria.
The main part of this project focused on finding a flexible material that could be used to integrate these nonharmful bacteria into living sensors. As no biodegradable alternatives to silicone where found that could be
placed directly on top of the bacteria and allowed for the formation of structural colour underneath, the
envisioned label involves a physical headspace between the top material and bacteria. Additionally, efforts
were directed towards establishing an activation method to initiate bacterial growth exclusively during the
product’s use phase. In the final design of the LCL, Flavobacteria are integrated into the label in a dormant
state and activated as they come into contact with the moist nutrient layer inside the label.
The iterative design process and discussions within the consortium led to a proof of concept for a
Flavobacteria-based LCL as well as a set of design guidelines. Finally, recommendations are presented to
further develop these living biosensors, paving the way for future exploration and application of these living
microorganisms towards a circular economy where digital technology and organic systems merge.

What if living organisms communicated signals from the environment to us and thereby offered a sustainable alternative to electronic sensors?
Within the field of biodesign, designers and scientists are collaborating with living organisms to produce new
materials with ecological benefits. The company Hoekmine, in collaboration with designers, has been
researching the potential of flavobacteria for producing sustainable colorants to be applied on everyday
products. These non-harmful bacteria can change their form, texture and iridescent color in response to
diverse environmental factors, such as humidity and temperature. Here, billions of cells are sensing and
integrating the results as color. Therefore, Hoekmine envisions biosensors, which would minimize the use of
increasingly demanded electronic sensors, and thus, the implementation of scarce and toxic materials.
Developing a living sensor by hosting flavobacteria in a biobased and biodegradable flexible material offers
opportunities for sustainable alternatives to electronic sensors. Aiming to take this concept to the next level,
we propose a research collaboration between Avans, Hoekmine and a company specialized in biobased and
biodegradable labels, Bio4Life. Together with this interdisciplinary team, we aim to bridge microbiology and
embodiment design, and contribute to the development of a circular economy where digital technology and
organic systems merge in the design of Living Circular Labels (LCLs). Throughout the project we will use an
iterative approach between designing and testing LCLs that host living flavobacteria and additionally,
methods for the end user to activate the bacteria’s growth at a given time.