Switchable hydrophilic/hydrophobic antibacterial fibrous composites for biomedical application

In this study, novel pH responsive hydrophilic/hydrophobic breathable Janus fibrous composites were fabricated with N-halamine quaternary ammonium salt/polyhydroxybutyrate inside and pH sensitive polymer/polycaprolactone outside. After HCl treatment, the fibrous membrane shows well hydrophilicity and breathability, which is helpful for cell growth and proliferation, further accelerating wound healing. Moreover, the membrane has prominent antibacterial efficiencies, which can activate 99.95% of S. aureus and 99.99% of E. coli O157:H7 within 30 min. Notably, this membrane displays excellent hemostasis performance. After further NH4OH treatment, the membrane transforms different wettability and thus reduce bacterial adhesion by its hydrophobicity. Similarly, one side of membrane has hemostasis property, while another side possesses anticoagulant properties with high contact angle of blood, which can prevent blood permeate. Besides, the cell viability test illustrates that no pronounced toxicity to cells is observed. Therefore, the adjustable hydrophilic/hydrophobic material highly extends the application of Janus membrane as wound healing dressing.