Chitosan-based antibacterial microspheres loaded multifunctional Janus composite membranes with unidirectional biofluid transport, antioxidant and pH-responsive monitoring

Bacterial infection, management of wound exudate and monitoring of healing status are the most prominent problems in wound treatment, however, according to research findings, the large multifunctionality of dressings studied so far is relatively homogeneous, and making wound dressings with simultaneous antibacterial and antioxidant properties, unidirectional fluid delivery and monitoring of wound healing is still a challenge in current research. Here, based on electrostatic spinning and electrostatic spraying techniques, a multifunctional Janus composite membrane was prepared by combining a hydrophilic layer polyacrylonitrile@poly(dopamine) (PAN@PDA), a hydrophobic layer polycaprolactone@ curcumin/silk fibroin (PCL@CUR/SF), and a drug-carrying layer aminated mesoporous silica-chitosan/curcumin (MSN-NH2-CS/CUR) to exploit the difference in wettability between the layers, excess wound exudate was drained. Interestingly, the cumulative in vitro release rate of the composite membrane was 7.67% at 551 h. The antioxidant activity was 79.01% at 120 min. The antibacterial properties of the composite membrane against Escherichia coli and Staphylococcus aureus were about 98% and 99%, respectively, indicating the excellent drug retardation and antibacterial and antioxidant properties of the composite membrane. The color of the composite membrane slowly changed from yellow to orange-red when exposed to pH 6, 7.2, 8 and 9 buffers, indicating that the composite membrane can be used as a pH indicator in the wound healing process. MTT and cell adhesion experiments showed that the composite membrane has good cytocompatibility and is conducive to cell adhesion and proliferation. This multifunctional Janus composite membrane will be useful for wound management and treatment.