Dextran hydrogels degrading

Simonsen, L., Hovgaard, L., Mortensen, P.B., and Brondsted, H., Dextran hydrogels for colon-specific drug delivery. Degradation in human intestinal incubation models, Eur. J. Pharm. Sci., 3 329-337 (1995). 

Franssen, 0., Vandervennet, L., Roders, P, and Hennink, W. E. Degradable dextran hydrogels Controlled release of a model protein from cylinders and microspheres. J. Contr. Rel. 60 211-221, 1999. 

Franssen O, Vos OP, Hennink WE. Delayed release of a model protein from enzymatically degrading dextran hydrogels. J Control Release 1997 44 237-245. 

De Jong SJ, Van Eerdenbrugh B, Van Nostrum CF, Kettenes-van den Bosch JJ, Hennink WE. Physically crosslinked dextran hydrogels by stereocomplex formation of lactic acid oligomers degradation and protein release behavior. J Control Release 2001 71 261-275. 

Kamath, K.R. and K Park, Study on the release of invertase from enzymatically degradable dextran hydrogels. Polymer Gels and Networks, 3 (1995) 243-254. 

Recendy Kaplan and Park studied chemically crosslinked dextran hydrogels for application in the controlled deliveiy of bioactive proteins (Kaplan and Park, 1995). Dextran was functionalized by reacting it with glycidyl acrylate to introduce reactive double bonds. Upon exposure to y-irradiation the functionalized dextran formed a crosslinked gel which could be degraded by dextranase. 

PROTEIN RELEASE FROM ENZYMATICALLY DEGRADING DEXTRAN HYDROGELS... 

A biodegradable and biocompatible dextran hydrogel system has been developed of which the degradation time can be tailored between 2 days and 3 months. This chapter shows that hydrogels based on crosslinked dextrans have unique properties as protein releasing matrices. Both the release pattern (first-order, zero-order or biphasic) as well as the duration of the release can be controlled by an appropriate selection of the characteristics and the geometry of the hydrogel. 

Transparent hydrogels useful for adhesion inhibitors, tissue adhesives, wound dressings, hemostatics and embolisation materials are obtained from dextran methacrylates via polymerisation with N-isopropylacrylamide in DMSO in the presence of azobisisobutyronitrile [176]. A broad variety of new hydrogels with different sensitivities and tunable degradation behaviour is accessible by grafting L-lactide onto 2-hydroxyethyl methacrylate (HEMA) and binding this polymerisable group on dextran via activation with N,N -carbonyldiimidazole (CDI, Sect. 4.2.2) [177]. 

Van Dijk-Wolthuis WNE, Tsang SKY, Van Steenbergen MJ, Hoogeboom C, Hennink WE. Degradation and release behaviour of dextran based hydrogels. Macromolecules 1997 30 4639-4645. 

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