Formulation and evaluation of 3D-printed dressings loaded with curcumin and levofloxacin for wound healing application

Curcumin (CUR), traditionally used for wound healing, is a promising candidate for incorporation into wound dressings. To enhance its antibacterial efficacy, levofloxacin (LEVO), a broad-spectrum antibiotic effective against both gram-positive and gram-negative bacteria, was co-formulated. CUR and LEVO were incorporated into wound dressings using a semi-solid extrusion (SSE) 3D printing technique. The SSE approach minimised potential drug interactions and eliminated the use of organic solvents. Two different polymers, ethyl cellulose (ethocel) and corn protein (zein), were employed as the matrix materials and comparatively evaluated. The physicochemical and mechanical properties of the printed dressings were assessed, along with drug release profile and antimicrobial activity. Ethocel-based wound dressings demonstrated lower elasticity but higher fracture resistance due to superior tensile strength. In vitro release studies showed that the type of polymer (ethocel or zein) did not significantly affect the release profiles of CUR or LEVO. Antimicrobial assays revealed bacterial counts of <1 CFU/mL in all treated groups for ethocel-based wound dressing except the blank, confirming the antibacterial effectiveness of CUR, LEVO, and their combination against Staphylococcus aureus. The ethocel-CUR-LEVO group showed the most favourable wound healing response, characterised by increased epithelialisation, enhanced fibroblast migration, and reduced neovascularisation. These findings suggest that the CUR-LEVO-loaded ethocel-based dressing is a promising candidate for advanced wound care application.