Cobalt ferrite nanoparticles for bimodal hyperthermia and their mechanistic interactions with lysozyme

Magnetic nanoparticles find several applications in cancer therapy. We have synthesized cobalt ferrite nanoparticles (CFNPs) and evaluated them as agents for magnetic hyperthermia (MH) effect. The CFNPs were well characterized for size and morphology using TEM, FESEM, and DLS. They were in the size range 8-25 nm with a roughly spherical shape. They were ferrimagnetic with a saturation magnetization of 42 emu/g. They showed a temperature increase of 38 degrees Cwhen exposed to an alternating magnetic field, and also showed photothermal effect. These two modes of heating along with magnetic targeting make these CFNPs a suitable candidate for biomedical applications. Their interaction with the protein lysozyme was also investigated. UV/visible and fluorescence spectroscopy showed that the CFNPs bind strongly to the protein with the binding constant of the order 105. Time-resolved fluorescence studies validated binding between them. CD spectroscopy showed that protein's conformation changed upon binding to CFNPs with a decrease in the percentage of alpha-helix. Molecular docking studies were performed to find out the site of binding in the protein. (C) 2020 Elsevier B.V. All rights reserved.