Chitosan Hydrogels with Antibacterial and Antifungal Properties: Enhanced Properties by Incorporating of Plasma Activated Water

Plasma technology for generating activated water has garnered significant interest among researchers for its antimicrobial properties post-treatment. This study aimed to produce chitosan hydrogels incorporating various types and concentrations of plasma activated water (PAW) derived from tap water and purified water. Initially, the physicochemical properties of PAW, including pH, electrical conductivity (EC), and total dissolved solids (TDS), were assessed, revealing a notable decrease in pH and an increase in EC and TDS post-activation. Chitosan hydrogels were then synthesized using PAW and subjected to Fourier Transform Infrared Spectroscopy (FTIR), Thermal Gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM) analyses. Results indicated a minimal impact on the chemical structure of the hydrogels post-PAW addition. TGA and DSC results revealed differences between tap water-based hydrogels and purified water-based hydrogels, indicating the presence of impurities or minerals in tap water. SEM observations depicted morphological alterations with increased plasma exposure, potentially enhancing antimicrobial activity. In degradation and swelling tests, the hydrogels exhibited pH sensitivity, maintaining integrity in neutral and alkaline media while dissolving in acidic conditions. Hemocompatibility and antimicrobial efficacy were confirmed through hemolysis tests and antibacterial/antifungal assays, particularly in hydrogels with prolonged water activation times, attributed to reactive species in PAW. These findings underscore the potential of these hydrogels as disinfectants in the biomedical field.