Novel glycidyl methacrylated dextran/gelatin nanoparticles loaded with basic fibroblast growth factor: formulation and characteristics

Objective: To develop a novel efficient nanoparticulate carrier loaded with basic fibroblast growth factor (bFGF). Methods: Gelatin and glycidyl methacrylate-derivatized dextran (dex-GMA) were cross-linked and polymerized to form interpenetrating polymeric networks. The properties of the nanoparticles (NPs) were investigated as a function of the degree of dex-GMA substitution and the concentration of gelatin used in the preparation of the hydrogels. The morphology was observed with scanning eletromicroscopy and transmission eletromicroscopy. The swelling, degradation, and entrapment efficiency were also determined by dynamic evaluation methods in vitro. The protein release ratio and in vitro release kinetics were evaluated by routine procedure, and the biological activity of bFGF-loaded NPs was studied by cell proliferation assay, cell attachment, and cell function. Results: The NPs have a particle size of 320 /- 20 nm. bFGF was entrapped in the nanoparticles quantitatively (the encapsulation efficiency, 89.6 /- 0.9%). The bFGF in vitro release kinetics fitted to zero-order and Higuchi equations. Proliferation assay, attachment assay, and western blot showed that bFGF NPs had good biological effects on cultured bone marrow mesenchymal stem cells and could achieve a much longer action time than bFGF solution. Conclusion: These results suggested that a novel biodegradable dex-GMA/gelatin hydrogel NPs loaded with bFGF could be successfully developed from both dextran-and gelatin-based biomaterials.