Abstract
This study is an attempt to produce gadolinium-doped iron oxide nanoparticles for the purpose of utilization in magnetic fluid hyperthermia (MFH). Six gadolinium-doped iron oxide samples with varying gadolinium contents (GdxFe3−xO4,x=0, 0.02, 0.04, 0.06, 0.08, 0.1) were prepared using the hydrothermal method at 180 °C and high vapor pressure to incorporate gadolinium ions in the iron oxide structure. The samples were indexed as GdIO/x, with x varying from 0.0 to 0.1. The results reveal that gadolinium ions have a low solubility limit in the iron oxide lattice (x = 0.04). The addition of gadolinium caused distortion in the produced maghemite phase and formation of other phases. Based on X-ray diffraction (XRD) analysis and photoelectron spectroscopy (XPS), it was observed that gadolinium mostly crystalized as gadolinium hydroxide, Gd (OH)3 for gadolinium concentrations above the solubility limit. The measured magnetization values are consistent with the formed phases. The saturation magnetization values for all gadolinium-doped samples are lower than the undoped sample. The specific absorption rate (SAR) for the pure iron oxide samples was measured. Sample GdIO/0.04, pure iron oxide doped with gadolinium, showed the highest potential to produce heat at a frequency of 198 kHz. Therefore, the sample is considered to hold great promise as an MFH agent.
Highlights
Magnetic nanoparticles have been utilized for decades in various biomedical applications [1,2,3,4,5] including magnetic fluid hyperthermia (MFH) for cancer therapy [6,7,8], drug delivery [9] and as contrast agents for magnetic resonance imaging (MRI) [10,11] and as biosensors [12]
The results reveal that gadolinium ions have a low solubility limit in the iron oxide lattice (x = 0.04)
Comparing the obtained results with those reported in the literature shows that sample GdIO/0.04 can be efficiently used for hyperthermia without violating the safety criteria f .H = 5 × 109 kA/ms [76] and that the specific absorption rate (SAR) value of maghemite was enhanced by gadolinium doping
Summary
Magnetic nanoparticles have been utilized for decades in various biomedical applications [1,2,3,4,5] including MFH for cancer therapy [6,7,8], drug delivery [9] and as contrast agents for magnetic resonance imaging (MRI) [10,11] and as biosensors [12]. The high vapor pressure and temperature attained by the hydrothermal route, which creates a supercritical environment, are assumed to assist the formation of the desired phase In this environment, Ostwald ripening is favored, and relatively large particles are formed with enhanced crystallinity [34] compared to their counterparts prepared by the coprecipitation method. The various oxidation states and the large number of potentially formed crystal phases [47] render the process of determining the obtained structure very challenging This is in addition to the fact that there are very few successful attempts in the literature to produce gadolinium-doped ferrite nanoparticles and, scarce few studies about its feasibility as an MFH agent [48]. The ability of the samples to produce heat upon exposure to AMF is tested
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
