Engineered Living Materials

Deciphering the mechanism of interaction between Cellulose producing bacteria and Graphene Quantum Dots
to develop Engineered Living Biomaterials

PI: Ahmad Allahbakhsh, Ph.D.

Advisory team:

Prof. Amin Shavandi

Universit´e libre de Bruxelles (ULB), ´Ecole polytechnique de Bruxelles, 3BIO-BioMatter, Belgium

Prof. Nikolaj Gadegaard

Division of Biomedical Engineering, James Watt School of Engineering, University of Glasgow, Glasgow, UK

Dr. Carmen Maria Ruiz Herrero

Aix-Marseille Université, Université de Toulon, IM2NP, Marseille, France

Physiochemical properties of hydrogels that define the application of these important porous biomaterials can be designed through the hydrogel fabrication process. In this project, a new green strategy for the fabrication of hyper-porous hydrogels with designable physiochemical properties will be presented. In this new strategy, graphene quantum dots (GQDs), as building blocks in the structure of the hydrogel, will be converted into GQDs colloidal aggregates, and the self-assembled GQDs colloidal aggregates will then be crosslinked via a network of bacterial cellulose nanofibers produced by bacteria. The product of this process will be a new class of hydrogel engineered living material with viscoelastic properties similar to the bacterial cellulose hydrogels, as well as the hierarchical porous structure and tunable surface physicochemical properties similar to the self-assembled GQDs hydrogels. Three main work packages will be followed in this project. In the first work package, the emphasis will be on interaction studies on the mechanisms of interfacial interactions involved in the attachment of bacteria to the surface of GQDs aggregates, as well as interaction mechanisms of physical interactions between bacterial cellulose macromolecules and GQDs aggregates. In the second work package, GQDs hydrogels will be fabricated by crosslinking GQDs aggregates via bacterial cellulose nanofibers prepared by the bacteria. Moreover, the biodegradability of fabricated GQDs hydrogels with human enzymes will be evaluated in the third work package. This project will provide important knowledge on the mechanism of interfacial interactions between living components and graphene-based nanostructures and will lead to the introduction of a new green strategy for fabricating porous hydrogels with tunable physicochemical characteristics.

Related Publications:

1- Ahmad Allahbakhsh, et al. Chemical Engineering Journal 467 (2023) 143472.

doi: https://doi.org/10.1016/j.cej.2023.143472

50 days’ free access URL (from May 17, 2023): https://authors.elsevier.com/a/1h5Vu4x7R2gMpN

Short description: In part of this work, we evaluated the microorganism growth of Nitzschia, E. coli, and S. aureus in the presence of conventional graphene-based hydrogels and aerogels. Our results confirm the hypothesis of our Civis Project that graphene-based hydrogels have bacterial growth inhibition properties and are not the best choices in the graphene family for fabricating bacteria-designed structures.

Related Masters Thesis Projects:

1- The crosslinking behavior of gelatin methacrylate biomaterial ink with graphene quantum dots aggregates for 3D-printing applications

Student: Quentin SPAEY (December 2022 – June 2023)

Supervisors: Amin Shavandi, Ahmad Allahbakhsh