A Deep Insight into the Mechanism of Production of Living Conducting Materials

Living cells are able fabricate complex structure starting from simple building blocks, offering new paradigms to create new hybrid materials by combing synthetic and living features. We have previously shown the capability of the living tissue-like organism, the freshwater polyp <i>Hydra</i> <i>vulgaris</i>, to produce fluorescent and conductive interface embedded into the animal tissues, starting from thiophene-based compounds, demonstrating the feasibility to use these organisms as biofactories of novel biocompatible and conformable bioelectronic interfaces [1-2]. Here we show that the potential of biofiber production is broadly valid in other biological systems, and showed that it can be promoted by several human and murine cell lines and by other invertebrate <i>in vivo</i> models (such as the sea anemone <i>Nematostella vectensis</i>). The cell type and organism developmental stage influences the fiber shape, amount and optical properties. In order to understand the mechanism underlaying the fiber biogenesis, on one side we performed a systematic chemical engineering approach to identify the structure/groups involved in the spontaneous fiber assembling. On the other, we performed several physical and chemical treatments to identify the cell machinery components involved in the biosynthetic process. Finally, by mean of advanced characterization methods and holographic imaging we shed light on the mechanism of biofiber production and the fine structure, paving the way to new bioengineering concepts to fabricate novel living conductive materials.<br/>[1] G. Tommasini, G. Dufil, F. Fardella, X. Strakosas, E. Fergola, T. Abrahamsson, D. Bliman, R. Olsson, M. Berggren, A. Tino, E. Stavrinidou, C. Tortiglione, Seamless integration of bioelectronic interface in an animal model via in vivo polymerization of conjugated oligomers, Bioactive Materials 10 (2022) 107-116.<br/>[2] M. Moros, F. Di Maria, P. Dardano, G. Tommasini, H. Castillo-Michel, A. Kovtun, M. Zangoli, M. Blasio, L. De Stefano, A. Tino, G. Barbarella, C. Tortiglione, In Vivo Bioengineering of Fluorescent Conductive Protein-Dye Microfibers, iScience 23(4) (2020) 101022.