Molecular Imprinting as a tool for producing Molecularly Intelligent Scaffolds for Tissue Engineering

Abstract

Tissue Engineering creates strategies capable of interacting with cells, to promote tissue regeneration. Cell adhesion is essential in cell communication and regulation, and cell-scaffold interactions occurring at the surface of the material are dependent on the biomolecules adsorbed. This knowledge promotes the biofunctionalization of biomaterials to enhance cellular response. Molecular Imprinting (MI) is an alternative to molecular recognition phenomena present in living systems, such as the antibody-antigen bonding, and has been proposed as a biofunctionalization method to improve scaffolds selectivity and recognition. The principle of MI is the polymerization of monomers and crosslinkers in the presence of the template molecule of interest and the subsequent removal of the template. The crosslinker enables the formation of specific cavities, which enables the material to recognize the template. The challenging in MI is the incorporation of biomacromolecules important for the wound healing. The imprinting of biomacromolecules holds drawbacks associated to the high molecular weight and complex structure. This work proposes a MI system based on methacrylated alginate imprinted with the model protein bovine serum albumin (BSA), using photo-polymerization. A non-imprinted polymer acting as control was also prepared by photo-polymerization without BSA. The effect of two crosslinkers and a monomer on mechanical properties of polymer discs was studied and the results revealed an improvement of the mechanical properties of crosslinked polymers. The template removal and rebinding capacity were also characterized for molecularly imprinted discs. The template removal showed results below 70%, most likely due to the amount of methacrylated alginate (4% w/v) and the bulk imprinting. Results concerning the capacity of the molecularly imprinted material to recognize BSA showed higher results when comparing to non-imprinted polymers. However, the system still needs to be improved, concerning the template removal and rebinding capacity. Still, it enabled the understanding of the effect of different crosslinkers on MI.