Abstract
The green synthesis of silver nanoparticles (AgNPs) using plant extracts presents a sustainable platform for multifunctional nanomaterials. This study reports the rapid, single-pot biosynthesis of AgNPs (B.gb-AgNPs) using the aqueous leaf extract of Barleria gibsonii. Phytoconstituents in the extract functioned as reducing and stabilizing agents, enabling efficient nanoparticle synthesis under optimized conditions. FT-IR, XRD, TEM, SEM, EDX, SAED, DLS, and zeta potential analyses confirmed the synthesis of predominantly spherical, face-centered cubic B.gb-AgNPs with nanoscale dimensions and biomolecular capping. The biosynthesized B.gb-AgNPs exhibited measurable antibacterial activity against both Gram-positive and Gram-negative bacteria, antioxidant capacity, and in vitro cytotoxic effects against MCF-7 breast cancer cells, with enhanced performance compared to the crude extract. In addition, the nanoparticles demonstrated effective catalytic activity in the degradation of methylene blue. Overall, this study extends current plant-mediated AgNP research by integrating phytochemical profiling, systematic synthesis optimization, and multifunctional evaluation, and identifies B. gibsonii as a promising bioresource warranting further investigation in sustainable nanotechnological research.
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Acknowledgements
The authors sincerely thank Prof. Dhanesh Patel, Director of the Office of International Affairs (OIA), The Maharaja Sayajirao University of Baroda, for his support. The authors gratefully acknowledge the Gujarat Biodiversity Board, Gandhinagar, for granting permission (Ref. No. GBB/Legal/1-6/2025-26, dated 15 November 2025) to collect the plant material. The authors gratefully acknowledge Prof. Padmanabhi S. Nagar, Department of Botany, The Maharaja Sayajirao University of Baroda, for the taxonomic identification of the plant material, and Prof. Dharmendra Shah, In-Charge of the BARO Herbarium, for the authentication and deposition of the voucher specimen. We thank Dr. Vandana J. Rao for assistance with XRD analysis and Prof. Devarshi Gajjar, Department of Microbiology and Biotechnology Center, for providing the bacterial strains (S. aureus and E. coli). The Department of Chemistry, The Maharaja Sayajirao University of Baroda, is acknowledged for FT-IR support under the DST-FIST program, and MNIT Jaipur for conducting the DLS, zeta potential, and HRTEM characterizations. The authors acknowledge the Micro–Nano Research and Development Center, Parul University (NAAC A+ +), for providing SEM–EDX facilities.
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Saif Saleh Mohsen Ali: Writing—original draft, Visualization, Validation, Methodology, Investigation, Formal analysis, Data curation, Conceptualization. Kanchan Dharmadhikari: Investigation, Methodology, Validation, Writing—review & editing. Kamartaha I. Saiyed: Writing—review & editing, Resources, Investigation, Methodology. Harishree Vasava: Writing—review & editing, Investigation, Methodology. M. A. Jowhari: Formal analysis (nanomaterial characterization and biomedical interpretation); Validation; Writing; review & editing. Pushpa Robin: Writing review & editing, Supervision, Project administration, Funding acquisition, Conceptualization.
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Ali, S.S.M., Dharmadhikari, K., Saiyed, K.I. et al. Ecofriendly synthesis of silver nanoparticles using Barleria gibsonii and evaluation of antibacterial antioxidant cytotoxic and catalytic activities. Sci Rep (2026). https://doi.org/10.1038/s41598-026-37330-3
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DOI: https://doi.org/10.1038/s41598-026-37330-3
