Composite Gels and Methods of their Use in Tissue Repair, Drug Delivery, and as Implants

Gel materials, particularly hydrogels, typically lose their mechanical strength and stiffness as they swell. This property  limits their use in both biological (e.g., cartilage and ECM repair) and non-biological (e.g., sealant) applications. Innovative materials in both medical and non-medical application areas are sorely needed.

Recent innovations in this space, from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), include self-reinforcing composite hydrogels. These composite materials comprise novel combinations of solvents, swellable crosslinked polymer particles, and crosslinked polymer networks or matrices, which confine them. Exemplary solvents include water and organic solvents, silicone fluids and oils and others known in the art. Exemplary swellable crosslinked microgel polymer particles could comprise hyaluronic acid (HA) or other proteoglycans, polyethylene glycol, dextran particles, a poly(acrylic acid), a poly(methacrylic acid), polystyrene sulfonate, polyvinylpyrrolidone (PVP), polyacrylamide, or combinations thereof. Exemplary confining polymer networks or matrices in which these microgel polymer particles are incorporated can include polyvinyl alcohol (PVA) and its copolymers (e.g., polyvinyl alcohol-polyvinyl acetate copolymer, polyvinyl alcohol – polyvinyl acetal copolymer, polyvinyl alcohol – polyvinyl butyral copolymer) and other matrices or networks such as cellulose derivatives (e.g., methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose). Tests of the innovative gels developed by NICHD scientists demonstrate that these gels have properties similar to, e.g., human cartilage – including load-bearing ability and demonstrating high self-reinforcement. The special properties of these gels also render them suitable for drug release to the intestines and other organs.

Researchers at NICHD welcome a wide variety of collaborative and licensing relationships. Possibilities include a cooperative research and development agreement (CRADA). The NICHD and NCI technology transfer center welcome non-exclusive or exclusive license agreements. They are eager to transfer rights in these technologies   to responsible commercial partners who will diligently move therapeutics and other applications towards commercialization.