Synthesis and Characterization of Chitosan-Alginate Nanocomposite Hydrogels containing ZnO Nanoparticles for Wound Dressing Applications

The management of chronic wounds and the prevention of bacterial infections is one of the essential challenges in biomedical engineering and healthcare. The use of novel dressings based on polymeric hydrogels has attracted considerable attention due to their ability to absorb wound exudate and simulate the extracellular matrix (ECM). The objective of this research is to design and fabricate a biocompatible nanocomposite scaffold using natural polymers chitosan and alginate, reinforced with Zinc Oxide (ZnO) nanoparticles, to improve mechanical properties, control the swelling rate, and provide antibacterial activity. To achieve this goal, a chitosan solution (۲% w/v) and sodium alginate solution were prepared and mixed. ZnO nanoparticles were incorporated at various weight percentages (۱, ۳, and ۵ wt%) and dispersed using ultrasonic waves. The samples were then converted into spongy scaffolds using the freeze-drying method. The chemical structure and interaction between the components were evaluated by Fourier-Transform Infrared Spectroscopy (FTIR) (Fig. ۱). Slight shifts in characteristic peaks, particularly in the ۳۴۰۰ cm region, confirmed the successful formation of hydrogen bonds between the ZnO nanoparticles and the polymer chains. Morphological examination by Scanning Electron Microscopy (SEM) showed a porous and interconnected structure with an average pore size of ۱۰۰-۱۵۰ μm, which is vital for cell infiltration and nutrient exchange. Furthermore, the swelling behavior of the scaffolds was studied in Phosphate Buffered Saline (PBS). The equilibrium swelling ratio decreased significantly with increasing nanoparticle concentration; for example, swelling reduced from ۱۲۵۰ ± ۴۵% (pure hydrogel) to ۶۱۰ ± ۳۵% (sample with ۵% ZnO). This reduction results from the nanoparticles acting as physical cross-linkers, limiting the mobility of the polymer chains and ensuring structural stability in the wound environment. In conclusion, the results of this study indicate that the Chitosan-Alginate-ZnO nanocomposite hydrogel, possessing suitable porosity, structural stability, and antibacterial potential, is a promising candidate for advanced wound dressing applications.

کلیدواژه ها:

Antibacterial ، Chitosan ، Hydrogel ، Tissue Engineering ، ZnO Nanoparticles