Double-layer PVA/chitosan-based curcumin-coated zinc oxide biofunctional wound dressing: GC-MS analysis, antimicrobial effect, molecular docking, and cytotoxicity evaluation

Abstract

This study focuses on the development and characterization of PVA (Polyvinyl alcohol) and chitosan (CHI)-based films that can be used as zinc oxide (ZnO) and curcumin (Cur) double-layered biofunctional wound dressings. In the study, PVA/CHI, PVA/CHI/ZnO, and PVA/CHI/ZnO/Cur films were prepared and characterized by various analyses. The first layer, consisting of PVA, CHI, and ZnO, provides biocompatibility and antimicrobial properties, supports tissue regeneration, and acts as a protective barrier against infections. The second layer was applied by electrospinning method to apply Cur, a natural compound found in turmeric with anti-inflammatory and antioxidant properties, and nanofibrous structures were formed on the first layer. FTIR, XRD, and DSC analyses show that ZnO and Cur were successfully integrated into the film structures and are consistent with the literature. High-resolution analytical electron microscopy (FESEM) reveals a homogeneous distribution of ZnO and Cur within the matrix, contributing to the uniform bioactivity of the films. Five different release kinetics models were compared for the PVA/CHI/ZnO/Cur double-layered wound dressing, and the R2 value for the Higuchi model was found to be 0.985. Antibacterial tests against Escherichia coli and Staphylococcus aureus demonstrate significant antimicrobial effects, with PVA/CHI/ZnO/Cur films exhibiting the largest inhibition zones (1.42 +/- 0.217 mm for E. coli and 1.34 +/- 0.114 mm for S. aureus), indicating enhanced antibacterial activity due to the synergistic effect of ZnO and Cur. Molecular docking of common components of Cur essential oils showed that antibacterial activity may be exerted by binding of curlone and tumerone with dihydrofolate reductase (DHFR) and filamentous temperature-sensitive protein Z (FtsZ). Overall, the developed bilayer biofunctional wound dressing offers a promising approach for future wound care applications, providing a multifunctional solution that accelerates the healing process while reducing the risk of infection.