A Mussel Mimetic, Bioadhesive, Antimicrobial Patch Based on Dopamine-Modified Bacterial Cellulose/rGO/Ag NPs: A Green Approach toward Wound-Healing Applications

A mussel mimetic transdermal patch was prepared using bacterial cellulose (BC), a green resource derived from Glucanoacetobacter xylinus (MTCC7795). To impart the mussel mimetic property, dopamine (DOPA), a catechol-containing compound, was used to modify the isolated BC via an amidation reaction between the carboxylated BC and DOPA, and the end product was successively characterized by 1H NMR and FTIR analysis. The free hydroxyl group of the DOPA moiety of DOPA-modified BC (BC-DOPA) was utilized to prepare BC-DOPA/rGO/Ag NPs, a composite film incorporating reduced graphene oxide/silver nanoparticles (rGO/Ag NPs). The antimicrobial action of the prepared film was determined against both Gram-positive (Staphylococcus aureus and Lysinibacillus fusiformis) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. The bactericidal property of the composite film was determined using the zone of inhibition (ZOI) method and live–dead assay (DAPI–PI analysis). The morphological transformation of bacteria upon the application of the composite film was observed through SEM analysis. The cell compatibility of the composite film over the NIH 3T3 fibroblast cell line was assessed through an XTT assay. The in vitro wound-healing assays over the NIH 3T3 cell line and A549 human lung epithelial cell line reveal that the presence of rGO and Ag NPs in the composite film accelerates the wound-healing process.