Effect of basic fibroblast growth factor released from chitosan-fucoidan nanoparticles on neurite extension

Exogenous growth factors are an integral part of an effective nerve tissue-engineering strategy. Basic fibroblast growth factor (bFGF) has a marked positive effect on angiogenesis and neuronal cell survival. However, bFGF is limited by its short half-life and easy degradation by enzymes. Therefore, in this study novel biodegradable chitosan–fucoidan nanoparticles (CS–F NPs) were designed to carry bFGFs and maintain their activities. The experimental results indicated that chitosan and fucoidan form stable nanoparticles approximately 200 nm in size via electrostatic interactions. Additionally, the effectiveness of nanoparticles is related to their chitosan:fucoidan weight ratio. The CS–F NPs control the release of bFGFs and protect bFGF from deactivation by heat and enzymes. In vitro cell studies demonstrate that CS–F NPs have no cytotoxicity to PC12 cells, as the concentration of NPs is 125 ng/ml. Moreover, the CS–F NPs significantly decrease the amount of bFGF needed for neurite extension. The cumulative release of bFGF from CS–F NPs at 24 h is 0.168 ng/ml, markedly lower than that in solution (4.2 ng/ml). Importantly, CS–F NPs are potential carriers for delivering bFGFs for nerve tissue engineering. Copyright © 2013 John Wiley & Sons, Ltd.