WO/1998/025653 is referenced by 1 patents.
This invention provides compositions for use in implanting into an animal comprising a biodegradable, biocompatible polymer which forms a hydrogel upon cross-linking. In a preferred mode, the polymer is cross-linked by multivalent ions; more preferably, a soluble salt of a multivalent ion and a sparingly soluble salt of a multivalent ion, these components being combined into a mixture which forms a partially hardened, injectable hydrogel, the consistency of the mixture being suitable for implanting the partially hardened hydrogel mixture into the animal, where the implanted, partially hardened hydrogel forms $i(in situ) a fully hardened hydrogel. Preferably, the mixture also contains a biocompatible sequestrant which competes with the biocompatible polymer for binding of the multivalent cross-linking ion. The composition may or may not contain living cells. The invention also provides methods for implanting the composition in an animal, optionally as an implant containing living cells.