Green Synthesis, Characterization, and Biological Evaluation of a Polyherbal-Based Chitosan-Fe₂O₃/ZnO Nanocomposite for Diabetic Wound Healing: In Vitro, In Silico, and In Vivo Study

Abstract

Diabetic wound healing is a complex process often delayed by hyperglycemia, oxidative stress, chronic inflammation, impaired angiogenesis, and defective tissue remodeling. This study aimed to evaluate the wound-healing potential of a polyherbal extract prepared from Syzygium aromaticum L. and Boswellia sacra, as well as Ch–Fe₂O₃/ZnO nanocomposite, in diabetic wound healing. The aqueous polyherbal extract was prepared by maceration and analyzed for its phytochemical composition, which revealed the presence of flavonoids, polyphenols, tannins, saponins, free quinones, mucilage, terpenoids, and alkaloids. Quantitative analysis confirmed its richness in total polyphenols and flavonoids. The Fe₂O₃/ZnO nanocomposite was synthesized and coated with chitosan, and its characterization by UV–Visible, FTIR, XRD, and SEM confirmed the structural, functional, and morphological characteristics of the final nanocomposite. In vitro results showed antioxidant, anti-inflammatory, and antibacterial activities against Escherichia coli and Staphylococcus aureus. The in silico study supported these effects through the interaction of Syzygium aromaticum compounds with Keap1 and boswellic derivatives with COX-2, with acceptable ADMET profiles. The in vivo study, performed using an alloxan-induced diabetic wound model in rats, showed that the untreated diabetic group had delayed wound healing, increased oxidative stress, and poor tissue repair. In contrast, treated groups showed improved wound closure, decreased MDA levels, increased GSH levels, and better histological organization. The Ch– Fe₂O₃/ZnO nanocomposite cream showed the best healing progression, with improved reepithelialization, collagen organization, fibroblast activity, vascularization, and skin regeneration. Overall, the results suggest that the polyherbal extract and Ch–Fe₂O₃/ZnO nanocomposite contributed to improving diabetic wound healing through antioxidant, anti-inflammatory, antibacterial, and tissue-regenerative effects.