Biogenic synthesis of silver nanoparticles using Sida cuneifolia leaf extract for enhanced antibacterial, cytotoxic, and anti-biofilm activities

Antimicrobial resistance (AMR) is one of the global threats that needs to be addressed. Nanotechnology represents a promising way to address this issue due to its multifaceted mode of action. This study aimed to synthesize and evaluate the antimicrobial and anti-biofilm properties of silver nanoparticles using <i>S</i>. <i>cuneifolia</i> leaves extract. The formation and properties of AgNPs were characterized using a UV-Vis spectrophotometer, an FT-IR spectrophotometer, TEM, and XRD. Disc diffusion and MIC were used to evaluate the antibacterial activity of AgNPs towards <i>E. coli</i>, <i>S. flexneri</i>, and <i>S. aureus</i>. The antibacterial action of silver NPs was observed using SEM, and cytotoxicity was assessed using the hemolysis assay. The anti-biofilm was evaluated against <i>E. coli</i> and <i>S. aureus</i>. From the results obtained, a sharp peak in the UV-Vis spectra centered at 419 nm was associated with AgNPs, while the sharp, distinct peaks in the powder diffractograms were linked to the face-centered cubic (fcc) of crystalline AgNPs. TEM micrographs confirmed their spherical morphology, with dimensions varying from 4 to 31 nm. The nanoparticles showed significant antibacterial and anti-biofilm activities against the tested isolates. Additionally, SEM confirmed that they could destroy the cell membrane and cause death. The biocompatibility of the synthesized AgNPs was safe at 100 μg/mL. Therefore, <i>S. cuneifolia</i> leaf extract has the potential to be an environmentally friendly substitute for the fabrication of Ag nanoparticles. The findings reveal that the synthesized nanoparticles could serve as a secure and effective alternative for addressing AMR.