Biomimetic hierarchical nanofibrous surfaces inspired by superhydrophobic lotus leaf structure for preventing tissue adhesions

Undesirable tissue adhesions remain one of the most common and dreaded postoperative complications. Biocompatible nanofibrous mats with antiadhesive surfaces represent a promising barrier method for preventing the formation of adhesions. The material developed in this work was inspired by the natural superhydrophobic lotus leaf nanostructure, which was mimicked by a unique combination of needleless electrospraying and electrospinning technology of poly-ε-caprolactone (PCL). The surface hydrophobicity of electrosprayed nanodroplets was further enhanced by cold plasma modification using the chemical vapor deposition (CVD) method with hexamethyldisiloxane (HMDSO). The treatment led to a successful decrease in surface wettability of our samples. Morphology (scanning electron microscopy), wettability (contact angle) and chemical composition (FTIR analysis) were observed for a period of six months to track possible changes; the obtained results verified the presence of HMDSO during the whole time period. Cytocompatibility was confirmed in vitro with 3T3 mouse fibroblasts according to the norm ISO 10993-5. Cell adhesion and proliferation were assessed in vitro by metabolic MTT assay and fluorescence microscopy after 4, 7, and 14 days. Antiadhesive behaviour was confirmed by atomic force microscopy and ex vivo by peel test 90° with intestinal tissue, the final structure has a great potential to reduce postoperative tissue adhesions.