Learning from Nature to Form New Organic Materials for Tissue RegenerationWednesday (08.05.2019) 09:15 - 09:45
The high demand for scaffolds capable of inducing tissue regeneration using minimally invasive techniques prompts the need for the development of new biomaterials. Herein, we investigate the ability of different compositions of short self-assembling peptides and polysaccharides to form extracellular mimicking scaffolds for tissue regeneration. For this aim, we used various polysaccharides such as hyaluronic acid, a major component of the extracellular matrix and alginate, a natural anionic biopolymer derived from brown seaweeds. These polysaccharides were incorporated with short peptides and amino acids building blocks that can form ordered assemblies such as nanotubes, nanospheres, and 3D-hydrogels with unique biological and physical properties. However, the control over the physical properties of the structure, including mechanical strength, degradation profile and injectability has remained challenging. In molecular self-assembly, the physical properties of the formed assemblies are directed by the inherent characteristics of the composing building blocks. Moreover, molecular co-assembly at varied stoichiometry substantially increases the structural and functional diversity of the formed assemblies, allowing to tailor both their architecture as well as their physical properties.
In line with polymer chemistry paradigms, we applied a supramolecular polymer co-assembly methodology to modulate the physical properties of hydrogel scaffolds. Using this approach, we developed a new peptide-based hydrogel with extraordinary rigidity, derived from a synergism between two different short peptides that were co-assembled. Due to its high stiffness, this hydrogel may serve as a scaffold for bone regeneration. Also, its tuneable mechanical properties may affect stem cells differentiation to different lineages as well. The co-assembly approach together with the incorporation of bone ceramics further enabled us to design a composite organic-inorganic scaffold with high affinity to hydroxyapatite, allowing bone tissue regeneration.
This work provides a conceptual framework for the utilization of co-assembly strategies to push the limits of nanostructures physical properties obtained through self-assembly.
 M. Aviv, M. Halperin-Sternfeld, I. Grigoriants, L. Buzhansky, I. Mironi-Harpaz, D. Seliktar, S. Einav, Z. Nevo, L. Adler-Abramovich, ACS Appl. Mater. Interfaces 2018, 10, 41883-41891.
 M. Ghosh, M. Halperin-Sternfeld, I. Grinberg, L. Adler-Abramovich, Nanomaterials 2019, 9, 497.
 M. Halperin-Sternfeld, M. Ghosh, R. Sevostianov, I. Grogoriants, L. Adler-Abramovich, Chem. Comm. 2017, 53, 9586-9589.
 M. Ghosh, M. Halperin-Sternfeld, I. Grigoriants, J. Lee, K. T. Nam, L. Adler-Abramovich, Biomacromolecules 2017, 18, 3541-3550.