Biosynthesis of iron nanoparticles using Ageratum conyzoides extracts, their antimicrobial and photocatalytic activity

Metallic nanoparticles synthesized using aqueous plant extracts are environment-friendly, biocompatible, and highly stable. The aim of this study was to synthesize iron nanoparticles using aqueous Ageratum conyzoides extracts and evaluating their antimicrobial and photocatalytic properties. The particles were analysed using UV–Vis spectrophotometer, FT-IR Spectrophotometer, X-ray diffractometer and Scanning electron microscope. GC–MS profile of the extracts revealed presence of secondary metabolites which were further quantified to determine the total phenolic and total flavonoids content of the extracts. The antibacterial activity of the plant extract and the synthesized iron oxide nanoparticles was evaluated against five microorganisms using agar well diffusion method. Iron nanoparticles synthesized in a one step process observed using visible spectra and the functional groups present such as C=O were identified from IR spectrum. SEM–EDX profile identified presence of iron, oxygen, chlorine, calcium in the particles while XRD data revealed the particles synthesized were composed oxides of iron which had moderate activity against the selected microorganisms as compared to the antibiotic ciprofloxacin. The particles were able to photocatalytic degrade methylene blue with a degradation efficiency of 92%. The results obtained in this study confirms that Ageratum conyzoides can play an important role in the bioreduction of Fe ions to FeNPs which have moderate activity against microorganisms and can act as photocatalyst to degrade methylene blue.