Supramolecular Hybrid Hydrogels Composed of Zwitterionic or Cationic Polymers: Toward Advanced Burn Dressings

Burn injuries affect over 400,000 people annually in the U.S. and rank as the sixth leading cause of preventable injury-related death. Despite their severity and prevalence, an ideal wound dressing for burn treatment remains an unmet clinical need. Current dressings often adhere to the wound bed, requiring painful debridement that can delay healing and increase the risk of infection. Thus, there is a critical need for advanced wound dressings that are mechanically robust, biocompatible, and easily removable. In this study, we report the design and characterization of supramolecular hybrid hydrogels (SHHs) composed of zwitterionic or cationic (co)polymers cross-linked via cucurbit[7]uril (CB[7]) host–guest interactions and reinforced with clay nanosheets (CNSs). Two water-soluble (co)polymers, zwitterionic poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) and cationic poly(acrylamide- random -(3-methacrylamidopropyl)trimethylammonium chloride (PAM), were synthesized via free radical polymerization and incorporated into SHHs to explore the role of polymer charge and structure. The inclusion of CNSs significantly enhanced mechanical strength, yielding storage moduli up to 55 kPa in PAM-based SHHs. Rheological analyses revealed that SHH mechanical properties could be precisely tuned by varying polymer chemistry, component concentrations, and mixing order, particularly in PMPC-based formulations. Importantly, PAM- and PMPC-based SHHs demonstrated rapid, controllable dissolution in phosphate-buffered saline (PBS), with PMPC-based hydrogels dissolving more uniformly due to their reduced noncovalent cross-linking. These results demonstrate that polymer charge and structure can tailor SHH properties, offering promising strategies for the development of next-generation wound dressings and broader biomedical applications.