Open Porous Composite Monoliths for Biomedical Applications via Photocrosslinking of Low Internal Phase Nano-Emulsion Templates

Abstract

Highly cross-linked polyethylene glycol monoliths (HCPEG) with interconnected micro and nanoporosity are produced via photo-crosslinking of low internal phase emulsions (LIPE). Unlike previous works, this approach allows the pre-processing functionalization of both polymer matrix and porosity by loading both phases of the emulsion template with several active fillers, such as enzymes, semiconductive polymers, and metallic nanostructures. Importantly, both polymer matrix and porosity of the resulting composite HCPEG monoliths show neither serious cross-contamination nor morphological alterations. All in all, this material behaves like a network of nano/micro flasks embedded into a permeable media. Mechanical and dielectric properties of these composites HCPEG monoliths can be tuned by varying the content of fillers. Since these composite materials are produced by photo-crosslinking of LIPEs, they can be easily and rapidly processed into complex shapes like microneedles arrays through replica molding without detrimental modifications of the porous morphology. In principle, the proposed strategy allows us to fabricate medical devices. As proof of concept, we embedded glucose oxidase enzyme in the nanoporosity and the resulting composite porous material retained the catalytic activity towards the oxidation of glucose.