Preparation and characterization of Ag immobilized on magnesium zinc ferrite (MgZnFe2O4) magnetic nanoparticles functionalized by Ziziphus leaf extract and study of their applications

In this paper, we report a green synthesis of MgZnFe2O4@ZSC-Ag with a cheap and clean method. Ag ions was immolized on surface of MgZnFe2O4 modified with Ziziphus spina-christi extract (ZSC). The MNPs was thoroughly analyzed using Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Field emission-scanning electron microscopy (FE-SEM), Energy dispersive X-ray analyzer (EDS), Inductively coupled plasma-optical emission spectrometry (ICP-OES), Thermogravimetric (TGA), and Vibrating sample magnetometry (VSM) techniques. The catalytic activity of MgZnFe2O4@ZSC-M (M: Ag, Cu) were evaluated in the reduction of nitrophenols to aminophenols in the presence of NaBH4. The process of reduction of nitrophenols to aminophenols was determined using UV-Vis spectroscopy. The rate constant (K) calculated for 3-nitrophenol (1.25 s-1g-1 (MgZnFe2O4@ZSC-Ag), 1.37 s-1g-1 (MgZnFe2O4@ZSC-Cu) and 4-nitrophenol (0.58 s-1g-1 (MgZnFe2O4@ZSC-Ag), 0.52 s-1g-1 (MgZnFe2O4@ZSC-Cu). These catalysts offer several advantages, including easy separation using a magnet, short reaction times, suitable yield of products and the ability to reuse the catalyst for up to 15 runs. Also, the antibacterial activity of MgZnFe2O4@ZSC-M (M: Ag, Cu) were evaluated against gram positive and gram negative bacteria. MgZnFe2O4@ZSC-Ag inhibited an inhibition zone 8, 10 mm for E.coli bacteria and S.aureus bacteria, respectively. It was higher than the inhibition zone for MgZnFe2O4@ZSC-Cu (6 mm for both bacteria), MgZnFe2O4@ZSC (6 mm for both bacteria). Also, the inhibitory concentration (MIC) value for MNPs described that MgZnFe2O4@ZSC-Ag had a better result against of S.aureus bacteria (16 mg/L) in the comparison with MgZnFe2O4@ZSC-Cu, MgZnFe2O4@ZSC MNPs.