Tailoring Bulk Transport In Hydrogels Through Control Of Polydispersity In The Nanoscale Pore Size Distribution

摘要

Many applications of polymer hydrogels demand precise and reproducible control over the pore-network architecture, but coarse estimates of the mean pore size are typically the only tool available to guide selection of gels with optimal properties. Here we show that the nanoscale distribution of pore sizes (i.e., polydispersity) plays a fundamentally important and previously unappreciated role in directing diffusive transport of macro-molecular compounds within hydrogel carriers. By introducing an approach that enables both the average pore size and the pore size distribution to be quantified, we demonstrate how polymerization conditions can be tuned to produce gels of identical composition that are nearly indistinguishable in terms of mean pore size but display remarkably dissimilar release kinetics owing to differences in polydispersity. These results suggest that control of nanoporous polydispersity offers a new and powerful avenue to manipulate and tailor the properties of hydrogel-based biomaterials. Nanoporous polymer hydrogels are indispensable in a wide array of products, particularly in the biomedical field, where they find use in applications ranging from controlled release of pharmaceutical compounds, to engineered tissue scaffolds, to separation of DNA and proteins.