Gentamicin-Linked Supramolecular Hybrid Hydrogels: Mechanically Robust Cucurbit[7]Uril-Based Networks for Prolonged...

Burn wound infections, caused by Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa), remain a major clinical challenge, delaying healing and increasing the risk of mortality. Gentamicin sulfate (GEN) is a broad-spectrum antibiotic widely used for infection control. However, conventional GEN-loaded hydrogels often suffer from burst release and inadequate mechanical strength for sustained wound coverage. Here, we report GEN-loaded (0.11-0.72 w/v%) supramolecular hybrid hydrogels (GEN-SHHs) in which GEN acts in a dual role as both an antimicrobial and a dynamic physical crosslinker through cucurbit[7]uril (CB[7]) host-guest interactions within a clay-reinforced hydrogel network. This polymer network gels within 5 s and achieves an exceptional elastic modulus (up to ∼270 kPa), the highest reported for CB[7]-based or antibiotic-crosslinked hydrogels. This integrated design achieves sustained GEN release for 14 days at concentrations above the minimum inhibitory and bactericidal thresholds for S. aureus and P. aeruginosa, yielding complete eradication (>99.999%) at GEN loadings ≥0.44 w/v%. Prolonged antimicrobial efficacy is further confirmed by persistent inhibition zones over two weeks. GEN-SHHs also maintain high cytocompatibility (>94% viability) with human dermal fibroblasts (HDFs) and epidermal keratinocytes (HEKs). These results establish GEN‑SHHs combining dynamic bonding, high stiffness, and durable antimicrobial performance for advanced infection-resistant wound dressings.