Plant Mediated Green Synthesis, Characterization, Magnetic Properties and Application of Ag-Fe Bimetallic Nano Materials Against Clinically Relevant Pathogens

In this study, a green synthesis of Ag–Fe bimetallic nanoparticles using an aqueous extract from the stem of Azadirachta indica was first noticed by the color change from translucent to brown. The same was characterized using UV and FT-IR analysis to ascertain its true formation before being subjected to antimicrobial study. The UV analysis revealed that, the maximum absorption peak was at absorbance of 0.3 with corresponding wavelength (λ max) at 400 nm. The FTIR spectrum of Ag-Fe BMNPs exhibits major peak positions at 2311.94 cm-1,1633.72 cm-1, 1354 .46 cm-1 and 664.93 cm-1 which indicate the N-H stretching vibrations of amines and O-H stretching of hydroxyl groups of alcohols and phenols. Intense peak at 1633.72 cm-1 might possibly due to C=O stretching of amide group. During the antimicrobial investigation, augmentin was used as control throughout at concentration of 300μg/L. Different concentrations of 100, 200, 300, 400 and 500μg/L of Ag-Fe BMNPs was tested against each microbe. With an increase in Ag-Fe BMNPs concentrations of all the pathogens, the inhibitory zone increases. The zones of inhibition for P. aeruginosa, S. aureus, C. albicans, and A. niger were 25.55 mm, 20.52 mm, 19.66 mm, and 17.99 mm, respectively, at a higher dose of 500μg/L. An indication that the synthesized Ag-Fe BMNPs may be used in the treatment of infections caused by clinically relevant drug-resistant strains. Furthermore, the synthesized nanomaterials were found to be paramagnetic.