Properties and antibacterial activity of MnFe2O4 nanoparticles obtained by pulsed laser ablation in liquid

Abstract

In this study, MnFe2O4 nanoparticles (NPs) were fabricated via pulsed laser ablation in liquid. Chemical and structural composition, microstructure, magnetic and antibacterial properties were characterized. Spinel was found as the main crystalline phase, while Fe2O3 and Mn2O3 were observed as the major secondary phases, all identified by X-ray diffractometry (XRD). Observation by Transmission Electron Microscopy (TEM) indicated that most of the nanoparticles were spherical in shape and found in agglomerates, most likely because of their magnetic nature. Moreover, Fast Fourier Transform of selective area electron diffraction patterns pointed at the existence of crystalline particles. The coercive field (Hc) and saturation magnetization (Ms) values determined for these NPs were found to increase with decreasing temperature. Their antibacterial properties were evaluated using the viable bacteria counting technique (colony) for MnFe2O4 concentrations of 100 and 300 μg/mL with Bacillus subtilis, Salmonella typhimurium, Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli strains.