Enzyme-responsive Polymer Hydrogels
BACKGROUND Biomaterials, either natural or synthetic, can be used to replace tissue, organ or body function for a period of time either for permanent implantation (heart valves), long-term application (contact lenses) or short-lived application (wound-dressings, catheters, etc.). They also have other biorelated applications. Hydrogels are based on either natural or synthetic polymers and are hydrophilic. As a result they swell in water and can expand up to 1000 times their weight, resulting in porous materials with internal water-filled cavities. Their internal environment is ‘water-like’, making them compatible with biological systems. THE TECHNOLOGY Smart (or intelligent, responsive, programmable) hydrogels change their physical properties (swelling/collapse) in response to a stimulus, such as pH, ionic strength, solvent polarity, temperature or electric field. Dr. Rein Ulijn of the School of Materials at the University of Manchester has developed bio-responsive hydrogels that change their properties when triggered by the selective catalytic action of a target enzyme. This approach allows for disease-specific enzymes to be targeted thus paving the way to localised therapeutics. Contact In the above example, hydrogels that have been functionalised with charged peptide linkers cause repulsion of polymer chains (due to electrostatics) and the hydrogel swells (left-hand side). In the presence of specific enzymes the peptide units are selectively cleaved, the gel collapses and traps the interacting enzyme (centre). Thus, specific enzymes can be absorbed selectively by the hydrogel unlike other ‘smart’ hydrogels which are non-selective (rhs: control vs enzyme). Whilst other smart hydrogel systems require conditions that may be disruptive to biological systems these work under mild conditions and at pH 5 –8. KEY BENEFITS• Biocompatibility
• Hydrogels are versatile and easily designed for specific applications (programmable to respond exclusively to a target enzyme).
• Hydrogels are selective - only recognised enzymes are entrapped and inactivated
• 3D wound-management systems
• Low-cost materials APPLICATIONS, MARKETS AND ADVANTAGES
• Healthcare e.g. targeted removal of disease-related enzymes
• Wound-healing where treatment is accelerated by removal of over-expressed enzymes ($5bn p.a. market)
• Coating disposable implants, e.g. catheters ($5.4bn p.a. market)
• Anti-inflammatory coating of intravenous catheters to reduce rejection
• Treatment of gingivitis ($1.5bn p.a. market) by removal of gum-disease related enzymes using oral gel formulation
• Medical sensors, e.g. glucose, enzyme immunosensors and fluophor biosensors
• Biocatalysis e.g. smart separations for the recovery of valuable enzymes INTELLECTUAL PROPERTY An international patent has been filed. OPPORTUNITY The technology is currently at an early-stage where ‘Proof-of-concept’ has been demonstrated. We seek a licensee/collaboration partner to assist in the development and commercialisation of this technology.
Type of Offer: Licensing
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