Impact of Nanoparticles Synthesized From Azadirachta indica (A. Juss) for Targeted Control of Malarial, Dengue, and Filariasis Vectors With Minimized Aquatic Toxicity

In the present study, biogenic silver nanoparticles (AgNPs) synthesized using Azadirachta indica leaf extract were evaluated for their toxic effects on both target and non-target species. The botanical synthesized nanoparticles were tested against Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus and non-targeted species Artemia salina and Eudrilus eugeniae at 24 h posttreatment. AgNPs were characterized using the following analytical techniques: UV-Vis spectroscopy, FT-IR, x-ray diffraction (XRD), energy-dispersive x-ray spectroscopy (EDX), and scanning electron microscope (SEM) analysis. Results showed that AgNPs caused larvicidal activity with 90.66% mortality in An. stephensi, 97.33% in Ae. aegypti, and 93.33% in Cx. quinquefasciatus at 24 h posttreatment. A. indica-derived AgNPs had lower LC₅₀ (lethal concentration 50) and LC₉₀ (lethal concentration 90) values of 44.803 and 252.886 ppm/mL in An. stephensi, 18.358 and 189.553 ppm/mL in Ae. Aegypti, and 36.492 and 219.800 ppm/mL in Cx. quinquefasciatus, respectively. Furthermore, AgNPs demonstrated lower toxicity effects with 50.66% mortality in A. salina and 38.66% mortality in E. eugeniae at 24 h posttreatment. Additionally, they exhibited lower LC₅₀ and LC₉₀ values of 240.996 and 533.618 ppm/mL in A. salina and 301.122 and 548.944 ppm/kg in E. eugeniae at 24 h posttreatment, respectively. The findings conclude that green-synthesized AgNPs from plants offer a promising, cost-effective, and target-specific alternative for eco-friendly mosquito larvicides. Future work should focus on developing these plant-based agents with minimal non-target toxicity to support sustainable pest control. Further research may explore large-scale applications and assess the long-term environmental impacts of AgNPs in integrated vector management programs.