Melt electrowritten poly(caprolactone) lattices incorporated with silver nanoparticles for directional water transport antibacterial wound dressings

Excessive biofluid covering wounds will result in serious infection, which may delay the healing of the wounds. To manage wound exudate in time and prevent bacterial infection, an antibacterial wound dressing featured with directional water transport is proposed in this study. A high-resolution poly(caprolactone) (PCL) lattice prepared by melt electrowriting (MEW) acted as the hydrophobic inner layer and a cotton pad was used as the hydrophilic outer layer. Silver nanoparticles (AgNPs), which have antibacterial properties, were embedded into the PCL matrix by a green synthesis strategy. The fabricated MEW PCL lattices showed a highly regular structure in both macro- and micro-morphologies and the addition of AgNPs showed no significant impact on the moisture management of the bilayered wound dressing (all samples exhibited high one-way transport index, R > 850%). The antibacterial activity was directly proportional to the concentration of AgNPs. The MEW PCL lattices containing 2 wt% exhibited 100% and 96.96% antibacterial ability against E. coli and S. aureus, respectively. In addition, the cell viability of the MEW PCL lattices containing 2 wt% AgNPs was more than 70% after incubation for 24 h, 48 h, and 72 h, indicating that the cytocompatibility was acceptable. Although the mechanical properties of the MEW PCL lattices decreased with the addition of AgNPs, the lattice containing 2 wt% AgNPs still showed 118% elongation, which was also a sufficient elasticity for wound dressing. The successful preparation of this functionalized wound dressing would be valuable for the design of biomedical textiles.