Periodic Reporting for period 2 - BiTe (Sym-Bionic Matter: developing symbiotic relationships for light-matter interaction)
Période du rapport: 2022-10-01 au 2023-09-30
With this project, we aim to understand how living unicellular organisms build symbiotic relationships to synergistically manipulate light and to develop new hybrid materials combining functional living building blocks within synthetic matrices. By bridging the gap between artificial and living matter, we can produce materials that have radically new functionalities “borrowed” from living organisms, which can be challenging to achieve with only synthetic systems alone. Additionally, such novel hybrid systems, being composed of cells and bio-compatible and bio-based matrices, will be inherently biodegradable and hence more sustainable. As an example, we envision the development of novel photonic pigments that change colour in presence of volatiles pollutants or autonomous self-shading coatings that change their absorption in function of light conditions, while simultaneously producing oxygen. These novel materials can be achieved by combining artificial matrices that can host and autonomously support the living organisms performing the function. The pigments can be developed by encapsulating into symbiotic-hydrogels structural coloured bacterial colonies that change colour by sensing the external environment, while self-shading coatings can be achieved by maintaining motile phototactic cyanobacteria into soft-matrices. Such functionalities are challenging to achieve with traditional materials and often requires building blocks that are energetically expensive to produce and not sustainable.
Since the beginning of the project we have been working to develop platforms that are compatible with the simultaneous growth of the organisms and allow the continuous monitoring of their interaction and their response to light. By co-culturing cellulose producing bacteria and microalgae with the addition of cellulose nanocrystal (CNC) suspension, we managed to get a robust living hybrid bio-material, with very high cell viability. This result constitutes a true breakthrough in the field. Since this method is scalable and the material is photosynthetic, self-healing and regenerative, we expect it to bring many real economic benefits and possible applications in photobioreactors.
Moreover, we have very good preliminary results for the formulation of hydrogels which will support the growth of structurally coloured bacteria with long colour persistence. We have also developed a biopolymer-based aqueous formulation that allows these bacteria to propel themselves without a solid surface. With these two exciting achievements, it is now possible to encapsulate these bacteria together with the biopolymer formulation in double emulsions to expect colour colony formation inside the droplet. At the end of the project, we expect to be able to fix the colour colony formed inside the droplet to produce permanent photonic pigments, as a sustainable and environmental-friendly alternative to conventional pigments.
We have also obtained some promising preliminary results on light management in microalgae. Our single-cell studies on transmittance and reflectance of Chlorella vulgaris have revealed patterns in relation to cell size and culture density. It has also revealed that the density of the culture from which the cells were removed has a substantial impact on the absorption spectra of individual cells. It highlighted that two cells of the same age from different densities of culture will have different absorption patterns, with cells from denser cultures showing overall higher absorption across the visible spectrum.
Moreover, we have very good preliminary results for the formulation of hydrogels which will support the growth of structurally coloured bacteria with long colour persistence. We have also developed a biopolymer-based aqueous formulation that allows these bacteria to propel themselves without a solid surface. With these two exciting achievements, it is now possible to encapsulate these bacteria together with the biopolymer formulation in double emulsions to expect colour colony formation inside the droplet. At the end of the project, we expect to be able to fix the colour colony formed inside the droplet to produce permanent photonic pigments, as a sustainable and environmental-friendly alternative to conventional pigments.
We have also obtained some promising preliminary results on light management in microalgae. Our single-cell studies on transmittance and reflectance of Chlorella vulgaris have revealed patterns in relation to cell size and culture density. It has also revealed that the density of the culture from which the cells were removed has a substantial impact on the absorption spectra of individual cells. It highlighted that two cells of the same age from different densities of culture will have different absorption patterns, with cells from denser cultures showing overall higher absorption across the visible spectrum.
The results obtained from these studies contribute to a fundamental understanding of symbiotic behaviour in marine ecosystems and their evolution in the context of light management. At the same time, these findings equip the scientific community with methodologies that can be exploited in the wider context of synthetic ecology. The project paves the way towards the exploitation of living building blocks for the fabrication of new materials relevant to commercial applications.