Production and Characterization of Azadirachta indica-Mediated SiO₂ Nanoparticles and an Evaluation of Their Antioxidant and Antimicrobial Activities

Azadirachta indica leaf extract was used in the current study to create silicon dioxide (SiO₂) nanoparticles securely. The unique aspect of this research is to utilize the biomass of A. indica as a capping, reducing, and stabilizing agent to produceSiO₂ nanoparticles with potential antioxidant activity. The size, functional groups, shape, purity, and stability of the as-produced nanoparticles were analyzed using spectroscopic and microscopic assessments. In addition, the antioxidant and antimicrobial activity were determined by DPPH assay and agar well diffusion method. As-synthesized SiO₂ nanoparticles were spherical, extremely stable, and amorphous nanoparticles with an average size of 22 nm. FT-IR analysis reveals that the occurrence of Si–O confirms the formation of SiO₂ nanoparticles. The purity of silicon dioxide nanoparticles wa sinvestigated by EDX analysis through the presence of Si and O. Thermal stability was determined and investigated by TGA analysis. DPPH analysis and Agar well diffusion assay confirmed that A. indica-mediated SiO₂ nanoparticles show good antioxidant and antimicrobial activity. The end product of biogenic SiO₂ nanoparticles may be useful for the formulation of new drugs.