A modular approach to easily processable supramolecular bilayered scaffolds with tailorable properties.

Engineering of anisotropic tissues demands extracellular matrix (ECM) mimicking scaffolds with an asymmetric distribution of functionalities. We here describe a convenient, modular approach based on supramolecular building blocks to form electrospun bilayered scaffolds with tailorable properties. Polymers and peptides functionalized with hydrogen-bonding ureido-pyrimidinone (UPy) moieties can easily be mixed-and-matched to explore new material combinations with optimal properties. These combinatorial supramolecular biomaterials, processed by electrospinning, enable the formation of modular fibrous scaffolds. We demonstrate how UPy-functionalized polymers based on polycaprolactone and poly(ethylene glycol) enable us to unite both cell-adhesive and non-cell adhesive characters into a single electrospun bilayered scaffold. We furthermore show that the non-cell adhesive layer can be bioactivated and made adhesive for kidney epithelial cells by the incorporation of 4 mol% of UPy-modified Arg-Gly-Asp (RGD) peptide in the electrospinning solution. These findings show that the UPy-based supramolecular biomaterial system offers a versatile toolbox to form modular multilayered scaffolds for tissue engineering and regenerative medicine applications such as the formation of membranes for a living bioartificial kidney.