Enhancing Structural Stability and Drug Release Control in Xanthan Gum–Poly(vinyl alcohol) Hydrogel Films via Ferric Ion Crosslinking
摘要
This study investigates the development and characterization of xanthan gum/poly(vinyl alcohol) (XP) hydrogel films crosslinked with ferric ions via a dipping method for controlled oral drug delivery. The effects of ferric ion crosslinking on the physicochemical and mechanical properties of the films were systematically evaluated through swelling behavior, gel content, thermal and mechanical analyses, cytotoxicity testing, and in vitro drug release profiling using para-acetylaminophenol as a model drug under simulated digestive conditions. Crosslinking with ferric ions significantly enhanced the structural integrity of the films by reducing water uptake and improving gel stability in both simulated gastric (SGF) and intestinal fluids (SIF). Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) revealed restricted polymer chain mobility due to ionic interactions within the network. Mechanical testing showed increased tensile strength and Young’s modulus with higher crosslinking density. Cytotoxicity assays confirmed excellent biocompatibility, with high cell viability observed across all formulations. The films enabled controlled release of para-acetylaminophenol under simulated gastrointestinal conditions, with drug release kinetics suggesting a combination of diffusion-controlled and erosion-mediated mechanisms. These findings support the potential of Fe3+-crosslinked XP hydrogel films as stable and biocompatible carriers for sustained oral drug delivery.
Graphical Abstract