Enhanced wound healing with a bilayered multifunctional quaternized chitosan-dextran-curcumin construct.

This study introduces a novel bilayer wound dressing that integrates a quaternized chitosan-polyacrylic acid (QCs-PAA) sponge as the top layer with electrospun nanofibers containing curcumin as the bottom layer. For the first time, QCs and PAA were combined in an 80:20 ratio through freeze-drying to form a porous sponge layer with ideal structural properties, including 83 ± 6 % porosity and pore diameters of 290 ± 12.5 μm. For the bottom layer, five groups of nanofibers containing PAA, dextran, and curcumin were electrospun onto the porous sponge. All wound dressings were non-toxic and exhibited exceptional antibacterial activity against S. aureus and E. coli. All groups, particularly the QP/PD0.25Cur bilayer dressing, showed significant HaCaT cell adhesion. Angiogenesis assays confirmed a remarkable increase in blood vessel number and thickness in samples containing 0.25 w/w% curcumin, with vascular density increasing from 0.32 in the single-layer sponge to 0.54 in the QP/PD0.25Cur sample, representing a 68 % enhancement. In vivo studies demonstrated that within 14 days, wound healing was accelerated with the QP/PD0.25Cur bilayer dressing, achieving 96 % closure compared to other groups. The findings revealed that all fabricated bilayer sponge-nanofiber wound dressings, particularly the 0.25 w/w% curcumin sample, can be a suitable candidate for wound management.