Synthesis, Characterization, and Study of Thermal Response of Cu-Doped Fe3O4 Nanoparticles

Iron oxide nanoparticles (IONPs) have great importance due to their use in many biomedical applications such as contrast agents in MRI, repairing of tissues, detoxification of biological fluids, cell separation, drug delivery, immunoassay, and magnetic hyperthermia. One of the interesting properties of IONPs is to produce heat in the presence of an applied alternating magnetic field (AMF), the basic principle of magnetic hyperthermia. Here, we seek synthetic reproducibility and to optimize Fe3O4 NPs to use in magnetic hyperthermia applications. We compared the thermal efficiency of Fe3O4 NPs after doping with copper. Using co-precipitation methodology, pure and Cu-doped Fe3O4 NPs were synthesized at five different concentrations (2%, 4%, 5%, 8%, and 10%). X-ray diffraction (XRD) and scanning electron microscopy (SEM) have been used to study the crystal structure and surface morphology of nanomaterials. Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy, and UV-visible spectroscopy were used to investigate the functional group, vibrational and optical properties of NPs. The thermal response of doped and undoped Fe3O4 NPs was studied by using high-frequency electromagnet driver for hyperthermia applications (HFEDHA) at 53 kHz frequency and 270 Oe magnetic field strength. To check the effects of suspension medium and variation of NP concentration in the sample on heat response and on specific absorption rate (SAR) values, the hyperthermia studies have been investigated in three biological mediums water, glycerol, and agar at four different NP concentrations 2%, 5%, 7%, and 10%. Our results show that at 2% concentration of copper in Fe3O4 NPs gave better results in all three mediums. However, they showed greater heat response and the highest SAR value in water than glycerol and agar. Further, at the lower concentration on NPs showed better thermal efficiency than higher concentrations.