Polysaccharide-based, emulsion-templated, porous poly(urethane urea)s: Composition, catalysis, cell growth

Polysaccharides are abundant natural resources that are of interest for various biomedical applications. In addition to being biocompatible and biodegradable, these polymers can undergo a wide range of application-specific chemical modifications. Here, macroporous polymer monoliths based on four different polysaccharides (alginate, pectin, dextran, and chitosan) were synthesized using a relatively simple and straightforward procedure, templating within oil-in-water high internal phase emulsions (HIPEs). Interfacial step-growth polymerization between the components in the external aqueous phase (water, a polysaccharide, a surfactant) and a diisocyanate in the internal organic phase was used to synthesize a set of poly(urethane urea) polyHIPEs. The diisocyanate content, the nature of the polysaccharide, and the nature of the polymerization catalyst significantly impacted the porous structure. Cells growing in the amine-catalyzed polyHIPEs adhered to the walls, spread, and penetrated into the porous structures. This work serves as a blueprint for generating macroporous monoliths from the multitude of available polysaccharides.