Biosynthesis of iron oxide nanoparticles using leaf extract of Ruellia tuberosa: Antimicrobial properties and their applications in photocatalytic degradation.

Green synthesis of nanoparticles is one of the promising, ecofriendly and safer methods. Utilizing plant sources as reducing agents will replace the use of toxic chemicals for nanoparticle synthesis. In the present study FeONPs were synthesized using Ruellia tuberosa (RT) leaf aqueous extract, further characterization of FeONPs was performed using UV-vis spectroscopy analysis showing visible peak at 405 nm. The Fourier transform infrared spectroscopy (FTIR) proved the presence of Fe metallic ions. The structural characteristic using Field emission scanning electron microscopy with energy dispersive x-ray spectroscopy (FESEM-EDX) and Transmission electron microscopy (TEM) analysis revealed hexagonal nanorods with agglomeration. Dynamic light scattering (DLS) calculated the average size of FeONPs around 52.78 nm and differential scanning colorimetry (DSC) proved the stability of FeONPs till higher temperature of 165.52 °C. As an application part, the synthesized FeONPs showed potential antibacterial activity as individual and incorporating material over cotton fabrics against Gram negative and Gram positive pathogens. FeONPs showed higher antibacterial activity against Escherichia coli, Klebsiella pneumoniae and lesser antibacterial activity against Staphylococcus aureus. The photocatalytic ability of the synthesized FeONPs was demonstrated by the degrading crystal violet dye under solar irradiation upto 80%. Thus, FeONPs synthesized using Ruellia tuberosa could play a vital role in killing the bacterial pathogens and degrading dye for the bioremediation of wastewater from industrial and domestic sources.