Patent ID: 8859705

Claim:
A kit for forming a hydrogel, said kit comprising: a) a first aqueous solution or dispersion comprising: (i) at least one oxidized polysaccharide containing aldehyde groups, having a weight-average molecular weight of about 1,000 to about 1,000,000 Daltons and having an equivalent weight per aldehyde group of about 65 to about 1,500 Daltons, said first aqueous solution or dispersion containing from about 5% to about 40% by weight of the oxidized polysaccharide; and (ii) at least one thiol additive, wherein the thiol additive is water-dispersible, contains only one reactive thiol (SH) group, does not contain any reactive carboxylic acid, primary amine or secondary amine groups, and has a molecular weight in the range of about 60 Daltons to about 40,000 Daltons, said first aqueous solution or dispersion containing about 0.1% to about 20% by weight of the thiol additive; and b) a second aqueous solution or dispersion comprising (i) at least one water-dispersible, multi-arm amine wherein at least three of the arms are terminated by at least one primary amine group, said multi-arm amine having a number-average molecular weight of about 440 to about 200,000 Daltons, said second aqueous solution or dispersion containing from about 5% to about 70% by weight of the multi-arm amine; or (ii) at least one a water-dispersible, multi-arm amine in the form of a neat liquid wherein at least three of the arms are terminated by at least one primary amine group, said multi-arm amine having a number-average molecular weight of about 440 to about 200,000 Daltons; wherein the hydrogel has a decreased gelation time and a decreased degradation time compared to a hydrogel prepared with said oxidized polysaccharide and said water-dispersible, multi-arm amine in the absence of the thiol additive.