Cassia gum–chitosan polyelectrolyte films incorporating propolis and ZnO@MOF nanoparticles enhance antimicrobial activity and support wound healing

Abstract

Designing bioactive wound dressings that simultaneously provide antimicrobial protection and support tissue regeneration remains a significant challenge in wound management. In this study, a multifunctional biocomposite film based on a carboxylated cassia gum/chitosan polyelectrolyte complex incorporating propolis and ZnO@Metal–Organic Framework (ZnO@MOFs) hybrid nanoparticles (CCPZM) was successfully developed. Structural characterization confirmed the formation of a stable polyelectrolyte network, while the incorporation of propolis and ZnO@MOFs significantly enhanced the mechanical, physicochemical, and thermal properties of the films. The CCPZM formulations exhibited controlled swelling behavior (13.8%) within 24 h and a gradual degradation profile over 30 days, indicating suitable stability under wound-like conditions. Antibacterial evaluation demonstrated enhanced activity of the CCPZM films, with inhibition zone diameters of 15.6 mm against Escherichia coli and 23.8 mm against Staphylococcus aureus. In vitro biological assessments revealed high cell viability, along with improved cell adhesion and proliferation. Furthermore, hemocompatibility analysis showed a hemolysis rate below 0.5%, confirming the safety of the developed system. Among all formulations, CCPZM10 exhibited the most balanced performance, combining superior antibacterial activity, structural stability, and biocompatibility. Overall, the synergistic integration of propolis and ZnO@MOFs within the polyelectrolyte network resulted in a multifunctional platform with controlled physicochemical behavior and enhanced biological performance, highlighting its strong potential as an advanced wound dressing for tissue regeneration applications.