Phytochemical-Mediated Synthesis and Characterization of Silver Nanoparticles Using Mirabilis jalapa Leaf Extract and Their Antibacterial

Abstract

Silver nanoparticles (AgNPs) synthesized through green methods have garnered significant attention in nanomedicine due to their unique inorganic properties and potential for a wide range of biomedical applications, including drug delivery, wound healing, and antimicrobial therapies. This study presents a novel, eco-friendly method for synthesizing AgNPs using Mirabilis jalapa leaf extract, which functions as both a reducing and stabilizing agent. The leaf extract, rich in bioactive compounds such as triterpenes, alkaloids, flavonoids, steroids, and phenolic compounds, plays a critical role in the reduction of silver ions (Ag⁺) to form elemental AgNPs. The synthesized AgNPs were rigorously characterized using powder X-ray diffraction (XRD), UV–visible spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) analysis. UV–visible spectra exhibited an absorption peak in the range of 431–446 nm, indicative of the formation of polydispersed AgNPs with surface plasmon resonance, while XRD analysis confirmed their crystalline face-centered cubic (FCC) structure. SEM imaging revealed spherical and quasi-spherical morphologies, while EDX spectra confirmed the presence of silver with minimal contamination. Antibacterial activity, assessed using the agar well diffusion method, demonstrated significant inhibitory effects against Gram-positive and Gram-negative bacteria, although the nanoparticles showed reduced efficacy against Pseudomonas aeruginosa and Bacillus subtilis . These promising antimicrobial properties, coupled with the long-established use of silver in wound healing and infection management, highlight the potential of these AgNPs in biomedical applications. The novelty of this research lies in the use of M. jalapa leaf extract for the synthesis of AgNPs, offering a green and sustainable alternative to conventional chemical methods. Future studies should delve into optimizing the synthesis process for large-scale production, evaluating the in vivo efficacy of the nanoparticles, and exploring their interactions with a broader range of pathogens. This work paves the way for the development of green-synthesized AgNPs as effective, eco-friendly agents for infection control and wound care in nanomedicine, with the potential to significantly advance the field by offering safer, more sustainable solutions for clinical applications.