Eco-Friendly Synthesis and Evaluation of Silver Nanoparticles (AgNPs) Using Azadirachta indica: A Greener Approach to Boosting Antimicrobial Power  

Anita Singh¹, Neelu Singh², Neha Khare³

¹ Associate Professor, Department of Applied Science, Sagar Institute of Research and Technology, Bhopal, MP, India.

² Professor, Department of Applied Science, Sagar Institute of Research and Technology, Bhopal, MP, India.

³ Assistant Professor, Department of Applied Science, Sagar Institute of Research and Technology, Bhopal, MP, India.

Abstract

The rapid progress of nanotechnology requires the creation of production approaches that avoid toxic, traditional chemical reducers. This research presents a detailed look into the biological synthesis of silver nanoparticles (AgNPs) by employing the water-based leaf extract of Azadirachta indica (Neem). Phytochemicals in the extract, such as phenolics and terpenoids, serve as both stabilizers and reducing agents. The process was tracked via UV-Vis spectroscopy, identifying a specific Surface Plasmon Resonance (SPR) peak at 422 nm. Structural imaging through Transmission Electron Microscopy (TEM) verified spherical particles with a mean width of   22 nm, X-ray Diffraction (XRD) confirmed the particles possess a face-centered cubic (FCC) crystal form. Additionally, these AgNPs displayed notable antibacterial effects against both Gram-negative (E. coli) and Gram-positive (S. aureus) strains, with inhibition zones of 18 mm and 15 mm, respectively. This investigation highlights a budget-friendly, sustainable, and scalable approach for creating nanomaterials, providing a strong alternative to standard chemical and physical techniques.   

Keywords: Green synthesis, Nanotechnology, Silver nanoparticles, Azadirachta indica, Antimicrobial activity, Sustainability.

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