Pharmacodynamic evaluation of ash-zinc oxide nanoparticles: synergistic gel formulation for wound healing and anti-inflammatory applications.

Objective: This study aims to develop and evaluate the wound-healing and anti-inflammatory potential of Ash-ZnO NPs and Ash-ZnO NPs gel formulation, synthesized using Saraca asoca extract and stabilized in a chitosan matrix. The goal was to overcome the limitations of conventional ZnO nanoparticles, including instability, cytotoxicity, and uncontrolled release.Significance: Although ZnO nanoparticles possess antimicrobial and regenerative properties, their clinical utility is limited by aggregation and dose-dependent toxicity. The use of Saraca asoca, a medicinal plant rich in flavonoids and phenolics, provides a green synthesis approach that enhances nanoparticle stability and biological activity. Incorporation into a chitosan-based gel further improves topical application by enhancing adhesion, moisture retention, and sustained release. Chitosan also contributes additional healing benefits due to its intrinsic biocompatibility, antimicrobial activity, and role in tissue regeneration.Methods: Ash-ZnO NPs were synthesized through a green co-precipitation method and formulated into a chitosan hydrogel. In vitro assays, including MTT, scratch wound, and protein denaturation tests, were used to assess cytocompatibility, fibroblast migration, and anti-inflammatory potential. In vivo wound-healing efficacy was evaluated in rats using an excision model, supported by histopathological analysis.Results: The Ash-ZnO NPs gel exhibited 72.5% inhibition of protein denaturation and achieved 75.63% wound closure within 48 h. Histology confirmed organized tissue architecture and minimal inflammation.Conclusion: The Ash-ZnO NPs gel represents a promising, biocompatible wound-care formulation that enhances nanoparticle stability, modulates inflammation, and accelerates tissue repair, offering strong potential for clinical dermatological applications.