title: Controlled release of EGF and bFGF from dextran hydrogels in vitro and in vivo.
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 microg mL(-1) EGF and 0.1 microg 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.
authors.affiliation: Department of Biology, Hacettepe University, Beytepe, Ankara, Turkey.
authors.forename: Alper K
authors.initials: AK
authors.lastname: Dogan
authors.forename: Menemşe
authors.initials: M
authors.lastname: Gümüşderelioglu
authors.forename: Erol
authors.initials: E
authors.lastname: Aksöz
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D048271:Chitosan / Q000737:chemistry; D003911:Dextrans / Q000737:chemistry*; D004337:Drug Carriers; D016503:Drug Delivery Systems; D004811:Epichlorohydrin / Q000737:chemistry; D004815:Epidermal Growth Factor / Q000378:metabolism*; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism*; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D066298:In Vitro Techniques; D008297:Male; D008855:Microscopy, Electron, Scanning; D015233:Models, Statistical; D018919:Neovascularization, Physiologic; D051381:Rats; D017208:Rats, Wistar; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared; D013997:Time Factors
chemical_list: D001672:Biocompatible Materials; D003911:Dextrans; D004337:Drug Carriers; D004811:Epichlorohydrin; D016222:Fibroblast Growth Factor 2; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D004815:Epidermal Growth Factor; D048271:Chitosan