Drug delivery and in vitro biocompatibility studies of gelatin-nanocellulose smart hydrogels cross-linked with gamma radiation

Abstract

In this study, pH-sensitive gelatin hydrogels reinforced with cellulose nanocrystals (CNCs) from rice husk were fabricated by introducing gamma irradiation to induce green cross-linking method hydrogels. The properties of the hydrogels were studied at varied CNCs and pH. The hydrogels were characterized by fourier-transform infrared (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), rheology, swelling studies, scanning electron microscopy (SEM), drug loading and release analysis, as well as cytotoxicity tests. The addition of CNC improved both the thermal and dynamic mechanical properties of the hydrogels. The hydrogels were sensitive to changes in pH, and the highest swelling degree was observed at pH 3. The optimum swelling performance was obtained with gelatin/4CNC hydrogels. SEM images revealed that incorporation of CNC content up to 4% improved the porosity of the hydrogels. The drug release analysis using riboflavin as a drug model showed that gelatin/4CNC hydrogels released more than 70% of riboflavin in 12 h. In addition, hydrogels showed non-cytotoxic properties, suggesting their potential application in drug delivery systems.

Keywords

• Biocomposite
• pH sensitive
• Cellulose nanocrystals
• Cytotoxicity
• Bovine gelatin