Superhydrophobic coating constructed from rosin acid and TiO2 used as blood repellent dressing

Blood repellent dressings plays an important role in trauma medicine. However, such dressings have poor hemostatic efficacy, and can cause infection, rendering them unsatisfactory for clinical application. We prepared a durable superhydrophobic coating for blood repellent dressing based on rosin acid and TiO2 with a water contact angle of 155.7° and a sliding angle of 5°. The morphology and chemical composition of the coating were characterized by scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) and X-ray spectroscopy (XPS), respectively. The superhydrophobic coating can withstand at least thirty sandpaper abrasions and sixteen washing treatments without losing its superhydrophobic properties. Meanwhile, the superhydrophobic coating demonstrated excellent antimicrobial activities against Gram-positive Staphylococcus aureus (S. aureus) (with log reduction = 1.73) and Gram-negative Escherichia coli (E. coli) (with log reduction = 1.74) and effectively prevented biofilm formation. Besides, the excellent biocompatibility of the superhydrophobic coating was verified by hemocompatible and cytotoxic assays. Finally, it was confirmed that the superhydrophobic coating can reduce blood loss and allows for high air permeability in in vitro tests. The superhydrophobic coating based on rosin acid and TiO2 provides a simple way for preparing novel blood repellent dressings, which may have promising applications in wound dressings.