Characterization of dexamethasone loaded collagen-chitosan sponge and in vitro release study

The aim of the present work is the development of porous mucoadhesive bio-sponge as a vehicle for release of dexamethasone for the treatment of oral mucositis. The influence of mixing collagen with chitosan on crystallinity structure and thermal behavior of both polymers were investigated. The polymer blends and dexamethasone-loaded polymers were characterized by FT-IR, SEM scanning, and swelling ability. The release study of the drug from chitosan, collagen, and collagen-chitosan (1:1) sponges was carried out in vitro. X-Ray diffraction of the collagen-chitosan film showed a semi-crystalline structure, that has a great influence on drug release. DSC curve showed one endothermal peak for neat and hybrid polymer sponges, confirming there was no denaturation of collagen fiber, and there was no phase separation between polymers. FT-IR results showed the forming of electrostatic and H-bonding between collagen and chitosan and the forming of H-bonding between dexamethasone and studied polymers. SEM for sponges showed that adding collagen to chitosan increased pores size, dexamethasone was clearly shown immobilized on the surface of polymer films. Drug release from the hybrid sponge was faster than the chitosan sponge, which ended in 16 h, and was slower than the collagen sponge which ended in 5 h. The formulation based on collagen-chitosan (1:1) blend was able to control drug release within 10 h.