An eco-friendly plant-mediated synthesis of silver nanoparticles: Characterization, pharmaceutical and biomedical applications

The current study focused on green chemistry approach to synthesize eco-friendly AgNPs using an aqueous extract of peganum harmala leaves. The formed AgNPs were characterized using different spectroscopic and microscopic analyses: ultraviolet-visible spectrophotometry (UV-Vis), Fluorolog 3 spectrometry, transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FTIR), techniques using a Zetasizer. The resulted nanoparticles were screened for their biomedical and pharmaceutical properties. They investigated for antimicrobial activity against various strains of bacteria and fungi. The synthesized AgNPs showed a higher antibacterial potential against Gram negative pathogen E. coli with inhibition zone of 65 mm rather than both Gram positive pathogens S. aurous and B. cereus of inhibition zone 50 mm. Meanwhile, no inhibition zone was observed for E. faecalis. Furthermore, the formed AgNPs were applied to enhance the sensitivity and selectivity of the spectrophotometric determination of the antibiotic Rifaximin in bulk powder or tablet form with a lambda(max) of 340 nm. The proposed spectrophotometric technique for determining Rifaximin in the presence of silver nanoparticles showed a linear relationship in the concentration ranges of 5-80 mu g/mL and followed the linear regression equation A = 0.039C-0.166 (r = 0.9997), with low limits of detection and quantification of 1.75 and 5.0 mu g mL(-1), respectively. According to the ICH guidelines, the proposed technique was validated.