Biosynthesis of Nickel Nanoparticles Using Aqueous <scp> <i>Aerva lanata</i> </scp> Extract and Their Utilization in Antimicrobial Activity

The synthesis of nanoparticles typically involves sophisticated equipment, significant energy consumption, and the use of hazardous chemicals. However, there is a growing trend to adopt sustainable methods by leveraging plants and microorganisms for nanoparticle fabrication. In this study, Aerva lanata (A. lanata) extract was employed to synthesize environmentally friendly, highly stable, and biocompatible nickel nanoparticles (Ni NPs). Various characterization techniques were used to investigate the structural, optical, and morphological properties of the synthesized Ni NPs. UV-Vis spectra revealed a surface plasmon resonance (SPR) band at 450 nm, confirming their optical properties. XRD analysis indicated the formation of highly crystalline Ni NPs. FTIR spectroscopy identified the vibrational frequencies associated with the nanocomposites. SEM and EDX demonstrated the nanoparticles' uniform polygonal and spherical morphologies, with an average particle size up to 40 nm, while SAED patterns confirmed their crystallographic planes. The Ni NPs were evaluated for their antibacterial and antifungal activities against S. aureus, S. albus, K. pneumoniae, P. vulgaris, C. albicans, and C. tropicalis. The results showed that Ni NPs achieved 100% fungal inhibition and 85% bacterial inhibition, highlighting their potential as effective antimicrobial agents.