Controlled release of platelet-derived growth factor-BB from chondroitin sulfate-chitosan sponge for guided bone regeneration

Platelet-derived growth factor-BE (PDGF-BB) releasing porous chondroitin-4-sulfate (CS)-chitosan sponge was designed with an aim of controlling growth factor delivery in order to improve bone formation. Porous CS-chitosan sponge was fabricated by freeze drying and crosslinking aqueous CS-chitosan solution. PDGF-BE was incorporated into the CS-chitosan sponge by soaking CS-chitosan sponge into the PDGF-EB solution. CS-chitosan sponge retained a porous structure with a 150-200-mu m pore diameter that was suitable for cellular migration and osteoid ingrowth. Release rate of PDGF-BB could be controlled by varying the composition of CS in the sponge or initial loading content of PDGF-BB. CS-chitosan sponge induced increased osteoblast migration and proliferation as compared with chitosan sponge alone. Furthermore, the release of PDGF-EB from CS-chitosan sponge significantly enhanced osteoblast proliferation. These results suggest that PDGF-BE-releasing CS-chitosan sponge may be beneficial to enhance bone cell adaptation and regenerative potential when applied in wound sites. (C) 2000 Elsevier Science B.V. All rights reserved.