Development of 3D-printed chitosan/p-coumaric acid scaffolds for wound healing: antibacterial properties and drug release kinetics

Para-coumaric acid (P-CA), a plant-derived phenolic compound, exhibits potent antioxidant activity that counteracts oxidative stress, a key factor delaying wound repair. In this study, a novel biocompatible wound healing scaffold was developed by incorporating P-CA into a chitosan-based polymeric matrix using hot-melt extrusion (HME) combined with fused deposition modeling (FDM) 3D printing. Chitosan (CS), polyethylene oxide (PEO), and cryomilled polycaprolactone (PCL) were used to achieve optimal printability and mechanical strength. The physical mixtures were extruded (110 °C, 50 rpm, 2.5 mm die) and printed into scaffolds (20 × 20 × 1 mm, 80 % infill). The optimized formulation, PCL/CS/P-CA/PEO (35:20:10:35, %w/w), produced scaffolds with excellent dimensional accuracy and mechanical integrity. In-vitro drug release studies demonstrated a sustained release of P-CA over three days. Antibacterial testing against Escherichia coli (E.coli) showed no inhibition with PCL/PEO, while CS and P-CA provided moderate activity individually. Notably, their combination yielded the highest antibacterial effect, suggesting a synergistic effect. These results suggest that P-CA-loaded CS-based scaffolds can provide sustained drug delivery with enhanced antibacterial performance, offering promise for wound healing applications.