Abstract
In the present study, dextran‐epichlorohydrin hydrogels were employed as carriers for the controlled release of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF). The hydrogels were synthesized from 50% (by weight) monomeric cross‐linker, epichlorohydrin, containing dextran mixtures by intermolecular side‐chain reaction of dextran‐hydroxyl groups with epichlorohydrin‐epoxy groups. The hydrogel disks of 3‐mm diameter and 1.5‐mm thickness have a high swelling capacity (EWC = 650%) and enough mechanical stability for the studies in vivo. Impregnation of EGF and bFGF into the dried hydrogels was carried out by use of phosphate buffered saline solution (PBS, pH =7.4) containing 0.5 μg mL^−1^ EGF and 0.1 μg mL^−1^ bFGF, respectively. The in vitro release of growth factors was detected by fluorescence spectroscopy. The prolonged release of EGF is continued up to the 14th day, in comparison with a 26‐day release of bFGF. The in vivo studies were realized with subcutaneously implanted hydrogels in Wistar albino rats. The rate of neovascularization was analyzed statistically using one‐way analysis of significance with EGF and bFGF incorporated hydrogels. In conclusion, dextran‐epichlorohydrin hydrogels were shown to be an alternative delivery system for the release of growth factors. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005