| 主权项 |
1. A kit for forming a hydrogel comprising:
a) at least one oxidized polysaccharide containing aldehyde groups, said oxidized polysaccharide 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 1500 Daltons; b) at least one water-dispersible, multi-arm polyether amine wherein at least three of the arms are terminated by at least one primary amine group, said multi-arm polyether amine having a number-average molecular weight of about 450 to about 200,000 Daltons; and c) at least one oligomer of the formula:
R1-(PS)-R2wherein:
(i) PS is a linear polymeric segment comprising ethylene oxide monomers or a combination of ethylene oxide and propylene oxide monomers, wherein said ethylene oxide monomers comprise at least 50 weight percent of said polymeric segment;(ii) R1 is at least one nucleophilic group capable of reacting with aldehyde groups to form at least one reversible covalent bond;(iii) R2 is at least one functional group which is not capable of reacting with an aldehyde, a primary amine, a secondary amine, or R1 to form a covalent bond, such that said oligomer does not induce gelation when mixed in an aqueous medium with either (a) alone or (b) alone;(iv) said oligomer has a weight-average molecular weight of about 200 to about 10,000 Daltons; and(v) said oligomer is water soluble; and wherein said hydrogel has a decreased degradation time compared to a hydrogel formed under the same conditions in the absence of said oligomer. |
