Screen-printed glycine-functionalized fullerene/ZnO chitosan dressings for enhanced diabetic wound healing

Chronic diabetic wounds complicated by oxidative stress, excessive inflammation and bacterial infection remain a critical clinical problem. Glycine-modified fullerene (Gly-Ful) was prepared to enhance the water dispersibility and bioavailability of fullerene (C₆₀). In vitro tests confirmed that Gly-Ful suppressed the upregulation of pro-inflammatory genes in M1 macrophages following LPS stimulation, and relieved mitochondrial damage. It decreased the apoptosis rate of H₂O₂-injured HUVECs, mitigates oxidative damage, and restored cell migration and tube formation. Gly-Ful was compounded with antibacterial ZnO using sodium alginate (SA) as a binder and film-forming agent, and subsequently screen-printed onto a chitosan (CS) nonwoven fabric to prepare the Gly-Ful/ZnO@CS dressing. The material exhibited high antibacterial activity (98.44% for E. coli, 99.79% for S. aureus), good air permeability (1356 mm/s), fluid absorption capacity (1586%), water vapor transmission rate (3138.47 g/m²/day), and porosity (52.05%), as well as stable interface adhesion, ideal blood compatibility (hemolysis rate < 0.54%) and cytocompatibility. In db/db diabetic mice, the Gly-Ful/ZnO@CS treatment group achieved a wound closure ratio of 97.29% on day 10, which was 25.71% higher than that of the blank control group and 14.02% higher than that of the CS control group. Histological staining showed enhanced epidermal regeneration and collagen deposition, with no organ toxicity observed. This multifunctional dressing optimizes the diabetic wound microenvironment and provides a potential strategy for chronic wound treatment.