Eco friendly synthesis of silver nanoparticles using Azadirachta indica and their biomedical application

Abstract

Nanotechnology has emerged as one of the fastest-growing interdisciplinary fields due to its extensive applications in medicine, agriculture, electronics, catalysis, and environmental remediation. Among metallic nanomaterials, silver nanoparticles (AgNPs) have gained considerable scientific attention because of their unique physicochemical, optical, catalytic, and biological properties. Conventional physical and chemical methods used for AgNP synthesis frequently involve hazardous reducing agents, high energy consumption, and environmentally toxic by-products, limiting their biomedical applicability [1,2]. Consequently, green synthesis approaches utilizing biological resources have attracted substantial interest as sustainable and eco-friendly alternatives [3]. Azadirachta indica (Neem), a medicinal plant rich in flavonoids, terpenoids, polyphenols, alkaloids, tannins, and azadirachtin, has been extensively explored as a reducing and stabilizing agent for biosynthesis of AgNPs [4,5]. Neem-mediated AgNPs exhibit enhanced antimicrobial, antioxidant, antifungal, anti-inflammatory, anticancer, wound healing, biosensing, and drug delivery properties owing to synergistic interactions between silver and phytochemicals [6,7]. Despite significant advances, several challenges including variability in nanoparticle size, lack of standardized synthesis protocols, toxicity concerns, and limited clinical validation continue to hinder biomedical translation [8]. Unlike previous reviews focusing broadly on plant-mediated nanoparticle synthesis, this review critically emphasizes neem phytochemistry, mechanistic pathways of AgNP formation, characterization techniques, biomedical applications, toxicological considerations, clinical limitations, and future prospects. Furthermore, recent advances, research gaps, and translational challenges associated with neem-mediated AgNPs are comprehensively discussed to provide future directions for sustainable nanomedicine research.