Synthesis and Characterization of Hybrid Biodegradable Films From Bovine Hide Collagen and Cellulose Derivatives for Biomedical Applications

Biomaterials are used as wound dressings and scaffolds, which are generally required to disperse by resorption into the body after tissue generation. Most methods employ relatively toxic cross-linking agent. In this study, an attempt has been made to prepare hybrid biodegradable films from bovine collagen by combining with cellulose derivatives without employing a cross-linking agent. The bovine hide trimmings were converted into soluble collagen and blended with 25, 50, 75, and 100% (wt/wt) 2-hydroxyethyl cellulose. These blends were cast into thin films and were analyzed for structure, thermal, mechanical, and biostability properties. It was found that the dry hybrid films have improved tensile strength in the range of 22 +/- 4.6 to 58.9 +/- 4.3 MPa, compared to the pure collagen films. On the other hand, hydrated films exhibited reduced strength and improved elongation compared to dry hybrid films. The structure of select films was investigated using scanning electron microscope (SEM) both in wet and dry state and found that the pore distribution is more in the wet state with high cellulose concentration. Differential scanning calorimetric (DSC) analysis showed that the thermal stability of dry hybrid films was improved moderately while the hydrated hybrid films exhibited enhanced hydrothermal stability compared to pure collagen films. The infrared (IR) spectral analysis of hybrid films reveals the presence of functional groups from both collagen and cellulose, especially the signature peaks of collagen triple helical structure. The equilibrium swelling and in-vitro biodegradability analysis proved that the presence of cellulose derivative could noticeably improve the biostability of the hybrid films leading to controlled degradation compared to the pure collagen films. Cell interaction studies show good biocompatibility and increased cell growth on the hybrid films as a function of cellulose concentration, although collagen is sourced from bovine hide trimmings of leather industry.