Injectable hydrogel based on natural polymers for drug delivery and tissue engineering applications

Abstract

Injectable hydrogels have emerged as promising materials in biomedicine due to their unique properties, such as high-water content and similarity to the extracellular matrix, along with the advantage of in situ application via syringes, which optimizes treatment. In recent years, research has intensified in the pursuit of developing and enhancing polymeric materials suitable for injectable hydrogels, with a focus on natural polymers. In this context, the present work explored the potential of an injectable hydrogel based on chitosan and guar gum, both chemically modified. Different formulations of hydrogels composed of N-succinyl chitosan (NSC) and oxidized guar gum (OxGG) were evaluated for specific biomedical applications. All systems were extensively characterized in terms of chemical, physical, and morphological aspects. Initially, the impact of cross-linking concentration between the macromolecules on the material's properties was studied, focusing on biodegradability and biocompatibility. Subsequently, lidocaine was incorporated into the most promising formulation to investigate controlled drug release, aiming to develop an effective system for pain relief in patients after musculoskeletal surgeries, with results demonstrating prolonged lidocaine release. Finally, to enhance the mechanical properties of the hydrogel composed of NSC and OxGG for tissue engineering applications, bacterial cellulose nanofibers (BCF) were added to the formulation, which, through rheological and compressibility tests, showed significant improvement in the material's stability and mechanical properties. The results demonstrated the high potential of this system for various biomedical applications, especially in drug delivery and tissue engineering.