Gelatin-reinforced PCL nanofibers infused with thyme essential oil with multifunctional performance for wound...

Wound healing is a multifaceted biological process orchestrated by the interplay of microbial load, cellular dynamics, and extracellular matrix (ECM) remodeling. Electrospun nanofibers have gained significant attention in wound management owing to their ECM-mimicking architecture, high surface area, and capability for sustained and controlled drug delivery. In this study, polycaprolactone (PCL) nanofibers incorporated with varying concentrations (5-20%) of thyme essential oil (TEO) were fabricated and systematically characterized to evaluate their physicochemical and biological properties. Among the formulations, PCL_T15 (PCL with 15% TEO) exhibited optimal fiber uniformity and morphological integrity (ϕ =258.51 ± 44.83) without compromising electrospinnability. To further augment the biological functionality, a hybrid nanofiber system composed of PCL and GEL containing 15% TEO (PCL:GEL_T15) was incorporated into the PCL_T15 matrix. The inclusion of GEL enhanced fiber morphology, hydrophilicity (water contact angle reduced from 115.82° ± 1.72 to 38.67° ± 5.36), and the controlled release of TEO, thereby improving the overall bioactivity of the system. The PCL:GEL_T15 nanofibers exhibited superior antibacterial efficacy, achieving complete eradication of Staphylococcus aureus (MRSA) and Escherichia coli (E. coli) within 12-24 h along with >95% biofilm inhibition. Antioxidant assays confirmed pronounced free radical scavenging capacity (>90%) of the hybrid nanofibers. Bacterial viability and membrane integrity assessments confirmed membrane damage and cell death, with SYTO9/PI dual staining indicating loss of membrane integrity, further validated by increased cytoplasmic leakage and crystal violet uptake. Overall, the PCL:GEL_T15 hybrid nanofibers exhibit a synergistic combination of structural, antioxidant, and antimicrobial functionalities, establishing them as an advanced antimicrobial wound dressing material.