A biocompatible silver-loaded zeolite hydrocolloid dressing with rapid antimicrobial efficacy

Abstract

Silver-based dressings remain indispensable for the management of infected wounds, but their clinical utility depends on reconciling rapid antibacterial action with acceptable tissue compatibility. Herein, we report a lipid–hydrocolloid dressing incorporating a silver-exchanged Linde Type A (LTA) zeolite (ZeAg-4%), in which the zeolite framework provides defined ion-exchange sites and spatial confinement for regulated silver availability. ICP-MS analysis showed a silver loading of 14.98 ± 0.04 wt% in the zeolite, while the optimized dressing contained only 52 ± 3 µg cm⁻² silver, substantially lower than the tested commercial silver dressings. Despite this reduced silver loading, The ZeAg-4% produced rapid antimicrobial activity, with no recoverable E. coli after 2 h in the carrier assay and >90% reduction of S. aureus within 4 h. Time-resolved experiments linked recoverable silver concentration with bactericidal kinetics, and additional biofilm, infected-wound, cytocompatibility, irritation, sensitization, and systemic-toxicity evaluations further defined its efficacy and safety profile. These results support zeolite-mediated silver utilization as a practical strategy for developing low-silver-loading antimicrobial dressings with improved safety margins.