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

Abstract

Platelet-derived growth factor-BB (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-BB was incorporated into the CS–chitosan sponge by soaking CS–chitosan sponge into the PDGF-BB solution. CS–chitosan sponge retained a porous structure with a 150–200-μm 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-BB from CS–chitosan sponge significantly enhanced osteoblast proliferation. These results suggest that PDGF-BB-releasing CS–chitosan sponge may be beneficial to enhance bone cell adaptation and regenerative potential when applied in wound sites.