Green Synthesis and Bioactivity Screening of Zinc Oxide Nanoparticles: In Vitro Investigation of Wound Healing, Antioxidant, and Antibacterial Properties
Keywords:
Green synthesis, Zinc oxide nanoparticles, Antioxidant activity, Antibacterial activity, Wound healing, Plant-mediated nanoparticles, BiomedicineAbstract
Background: Zinc oxide nanoparticles (ZnO NPs) are increasingly explored in biomedicine due to their multifunctional properties. However, traditional synthesis methods involve toxic reagents and high energy input. Green synthesis using plant extracts offers an eco-friendly alternative, with phytochemicals acting as natural reducing and stabilizing agents. This study investigates the green synthesis of ZnO NPs and evaluates their antioxidant, antibacterial, and wound healing activities.
Methods: ZnO NPs were synthesized using aqueous plant extract, followed by characterization via UV-Vis spectroscopy (peak at ~375 nm), FTIR (evidence of phenolic and hydroxyl capping), XRD (hexagonal wurtzite structure; average size ~24 nm), SEM (spherical morphology), and EDX (elemental confirmation of Zn and O). Antioxidant activity was assessed via DPPH, ABTS, and FRAP assays, with IC₅₀ values compared to ascorbic acid. Antibacterial activity was tested using the agar well diffusion method against E. coli and S. aureus. In vitro wound healing potential was evaluated using a scratch assay on HaCaT cells over 48 hours. Data were statistically analyzed (ANOVA, p < 0.05).
Results: The ZnO NPs demonstrated potent antioxidant activity with an IC₅₀ of 49.2 µg/mL (DPPH), comparable to the standard. Antibacterial activity showed zones of inhibition of 18.2 ± 1.1 mm (S. aureus) and 15.6 ± 0.9 mm (E. coli) at 100 µg/mL. In wound healing assays, ZnO NPs achieved 82.4% closure at 48 h, significantly higher than untreated controls. Characterization confirmed nanoscale size, purity, and plant-derived capping.
Conclusion: Green-synthesized ZnO NPs exhibit strong antioxidant, antibacterial, and wound healing properties, indicating their potential in biomedical applications such as wound dressings and antimicrobial formulations. Further in vivo studies and formulation development are recommended.
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Agarwal, H., Kumar, S. V., & Rajeshkumar, S. (2020). A review on green synthesis of zinc oxide nanoparticles–An eco-friendly approach. Resource-Efficient Technologies, 5(1), 1–10. https://doi.org/10.1016/j.reffit.2019.12.003
Gunasekaran, T., Nigusse, T., & Dhanaraju, M. D. (2020). Zinc oxide nanoparticles: Mechanism of antibacterial action, toxicity and their applications in biomedical fields. Nanoscience and Nanotechnology: An International Journal, 10(3), 1–15. https://doi.org/10.5923/j.nn.20201003.01
Hassan, D., Omran, B. A., & Hassan, A. (2017). Effect of zinc oxide nanoparticles on burn wound healing in rats. International Journal of Current Microbiology and Applied Sciences, 6(4), 2443–2455. https://doi.org/10.20546/ijcmas.2017.604.284
Iravani, S. (2011). Green synthesis of metal nanoparticles using plants. Green Chemistry, 13(10), 2638–2650. https://doi.org/10.1039/C1GC15386B
Premanathan, M., Karthikeyan, K., Jeyasubramanian, K., & Manivannan, G. (2011). Selective toxicity of ZnO nanoparticles toward Gram-positive bacteria and cancer cells by apoptosis through lipid peroxidation. Nanomedicine: Nanotechnology, Biology and Medicine, 7(2), 184–192. https://doi.org/10.1016/j.nano.2010.10.001
Raghupathi, K. R., Koodali, R. T., & Manna, A. C. (2011). Size-dependent bacterial growth inhibition and mechanism of antibacterial activity of zinc oxide nanoparticles. Langmuir, 27(7), 4020–4028. https://doi.org/10.1021/la104825u
Sharma, D., Kanchi, S., & Bisetty, K. (2019). Biogenic synthesis of nanoparticles: A review. Arabian Journal of Chemistry, 12(8), 3576–3600. https://doi.org/10.1016/j.arabjc.2015.11.002
Sirelkhatim, A., Mahmud, S., Seeni, A., Kaus, N. H. M., Ann, L. C., Bakhori, S. K. M., Hasan, H., & Mohamad, D. (2015). Review on zinc oxide nanoparticles: Antibacterial activity and toxicity mechanism. Nano-Micro Letters, 7(3), 219–242. https://doi.org/10.1007/s40820-015-0040-x
Singh, R. P., Shukla, V. K., Yadav, R. S., Sharma, P. K., Singh, P. K., & Pandey, A. C. (2018). Biological approach of zinc oxide nanoparticles formation and its characterization. Advanced Materials Letters, 1(3), 232–237. https://doi.org/10.5185/amlett.2010.9162
Kumar, V., Yadav, S. K., Yadav, A., & Prasad, V. (2021). Applications of zinc oxide nanoparticles in biomedical, environmental and agricultural sectors: Recent advances. Materials Science for Energy Technologies, 4, 570–589. https://doi.org/10.1016/j.mset.2021.07.002
Padmavathy, N., & Vijayaraghavan, R. (2008). Enhanced bioactivity of ZnO nanoparticles—An antimicrobial study. Science and Technology of Advanced Materials, 9(3), 035004. https://doi.org/10.1088/1468-6996/9/3/035004
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