Adhesive Sponge Based on Supramolecular Dimer Interactions as Scaffolds for Neural Stem Cells

Improving cell-material interactions of nonadhesive scaffolds is crucial for the success of biomaterials in tissue engineering. Due to their high surface area and open pore structure, sponges are widely reported as absorbent materials for biomedical engineering. The biocompatibility and biodegradability of polysaccharide sponges, coupled with the chemical functionalities of supramolecular dimers, make them promising combinations for the development of adhesive scaffolds. Here, a supramolecular tactic based on (UPy)-modified polysaccharide associated with three-dimensional structure of sponges was developed to reach enhanced cellular adhesion. For this purpose, three approaches were examined individually in order to accomplish this goal. In the first approach, the backbone polysaccharides with noncell adhesive properties were modified via a modular tactic using UPy-dimers. Hereupon, the physical-chemical characterizations of the supramolecular sponges were performed, showing that the presence of supramolecular dimers improved their mechanical properties and induced different architectures. In addition, small-angle neutron scattering (SANS) measurements and rheology experiments revealed that the UPy-dimers into agarose backbone are able to reorganize in thinning aggregates. It is also demonstrated that the resulted UPy-agarose (AGA-UPy) motifs in surfaces can promote cell adhesion. Finally, the last approach showed the great potential for use of this novel material in bioadhesive scaffolds indicating that neural stem cells show a spreading bias in soft materials and that cell adhesion was enhanced for all UPy-modified sponges compared to the reference, i.e. unmodified sponges. Therefore, by functionalizing sponge surfaces with UPy-dimers, an adhesive supramolecular scaffold is built which opens the opportunity its use neural tissues regeneration.