Biodegradable cross-linkers having a polyacid connected to reactive groups for cross-linking polymer filaments

Abstract

Biodegradable cross-linkers are provided having a polyacid core with at least two acidic groups covalently connected to reactive groups usable to cross-link polymer filaments. Between at least one reactive group and an acidic group of the polyacid is a biodegradable region which preferably consists of a hydroxyalkyl acid ester sequence having 1, 2, 3, 4, 5 or 6 hydroxyalkyl acid ester groups. The polyacid may be attached to a water soluble region that is attached to the biodegradable region having attached reactive groups. The hydroxyalkyl acid ester group is preferably a lactate or glycolate. Polyacids include diacids, triacids, tetraacids and pentaacids, and the reactive group may contain a carbon-carbon double bond. A network of cross-linked polymer filaments having adefined biodegradation rate can be formed using the cross-linkers. The network may contain biologically active molecules, and can be in the form of a microparticle or nanoparticle, or hydrogel. The polymer filaments may be preformed polymer filaments of polynucleic acids, polypeptides, proteins or carbohydrates. The cross-linkers may be copolymerized with charged monomers such as acrylic monomers containing charged groups. Applications of the cross-linkers and network include controlled release of drugs and cosmetics, tissue engineering, wound healing, hazardous waste remediation, metal chelation, swellable devices for absorbing liquids and prevention of surgical adhesions.