Xanthan gum and chitosan polyelectrolyte hydrogels with self-reinforcement of Zn+2 for wound dressing applications

Abstract

A straightforward methodology was employed for the self-reinforcement of zinc ions (Zn+2) within the polyelectrolyte complexation of xanthan gum (XG) and chitosan (CS) using D (+)-glucuronic acid-δ-lactone (GDL) as an acidifying agent in aqueous environment. The self-reinforcement and polyelectrolyte complexation between XG and CS was primarily achieved by maintaining acidic conditions through the use of GDL. GDL produces H+ ions, not only in converting ZnO to Zn+2 ions but also in facilitating the polyelectrolyte complexation between XG and CS. The confirmation of Zn+2 self-reinforcement was evident through the disappearance of ZnO, as observed in Fourier transform infrared spectroscopy and X-ray diffraction patterns. The compressive properties of self-reinforced Zn+2 within XG-CS hydrogels were evaluated, and their compressive strength was found to depend significantly on the reinforcement of ZnO nanoparticles. Incorporating 1 wt% ZnO improved the compressive strength of the hydrogels, decreasing further with an increasing amount of ZnO (3 wt%), as confirmed by compressive analysis. Detailed SEM images conclusively demonstrated The hydrogels porous structure, and elemental analysis verified the presence of Zn+2 ions. The antibacterial activity of Zn+2 reinforced XG-CS hydrogel showed excellent antibacterial activity towards both positive and negative bacteria. Furthermore, the biocompatibility analysis was assessed through an in vitro study that confirmed good biocompatibility towards NIH3T3 fibroblast cells. Thus, a robust inhibitory effect of bacterial growth and biocompatibility of developed hydrogels hold promise in advanced wound dressings for infected wounds.