Bioinspired ferromagnetic CoFe2O4 nanoparticles: Potential pharmaceutical and medical applications

Abstract The primary goal of this work was to develop a cost-effective, non-toxic, eco-friendly, and simple approach for the green synthesis of CoFe2O4 nanoparticles (NPs) using Aloe vera leaf extract by the sol–gel auto-combustion method. In order to figure out their structural, morphological, and magnetic properties, the synthesized NPs were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscope (TEM), dynamic light scattering (DLS), zeta potential, and vibrating-sample magnetometer (VSM). XRD analysis showed that particles had a single-phase spinel crystalline structure with an average crystalline size of 33.5 nm. Under VSM studies, the produced NPs exhibit a soft ferromagnetic property. SEM revealed that the as-prepared NPs were agglomerated due to their magnetic behavior. To the best of our knowledge, the anticandidal, antibiofilm, antibacterial, and anticancer activities of CoFe2O4 NPs toward drug-resistant gram-positive and gram-negative bacteria, as well as fungal strains, have been comprehensively investigated for the first time. The synthesized NPs had a minimal inhibitory concentration of 0.25–0.75 mg/ml against the tested pathogens. CoFe2O4 NPs inhibited the biofilm formation by 37.3–61.8% in selected strains at concentrations of 0.125–0.5 mg/ml. It was observed that the NPs not only suppress biofilm formation but also eradicate established mature biofilms by 50.9–64.49% that was further supported by SEM. SEM analysis shows that NPs significantly inhibit the colonization and aggregation of tested biofilm strains. Light microscopic analysis revealed that NPs completely inhibit the development of hyphae and filaments in Candida albicans, which significantly attenuates their pathogenicity. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays and 4′,6-diamidino-2-phenylindole (DAPI) staining demonstrate that NPs significantly inhibit the proliferation of HCT-116 and HeLa cells. Furthermore, the SEM images of treated cells showed wrinkled and damaged cell walls, indicating the disruption and disorganization of the membrane. This study showed that the synthesized NPs were effective in inhibiting the growth of drug-resistant bacteria, candida, and their preformed biofilms as well. Thus, these NPs with broad-spectrum applications could be exploited in medical settings to diminish biofilm-based infections caused by these pathogenic strains.