Antibacterial\nand Antifouling Hybrid Ionic–Covalent\nHydrogels with Tunable Mechanical Properties

Abstract

Because\nof their self-recovery ability and fatigue resistance,\ndouble-network (DN) hydrogels with hybrid ionical–covalent\ncross-linking have received wide attention. In this work, by a simple\n“one-pot” method, a novel kind of hybrid ionic–covalent\nchitosan/poly­(sulfobetaine methacrylate) (CS/PSBMA) DN hydrogels was prepared. The\nhydrogels showed high tensile strength (2.0 MPa), strong elastic modulus\n(0.5 MPa), fast self-recovery ability as well as excellent fatigue\nresistance, high mechanical strength, and toughness retention rate\nafter soaking in water for 24 h. Additionally, the mechanical properties\nof the DN gels were enhanced after stretch and relaxation because\nof the rearrangement of the CS network. More excitingly, because of\nthe antifouling feature of PSBMA and the inherent antibacterial property\nof CS, the hybrid DN hydrogels demonstrated a “repel and kill”\neffect on microorganisms. The CS/PSBMA DN hydrogels may find potential\napplications in biomedical fields, such as artificial connective tissues,\nimplantable devices, and wound dressing.