Synthesis and magnetic properties of size-tunable MnxFe3−xO4 ferrite nanoclusters

Abstract

We report the synthesis and characterization of size-tunable MnxFe3−xO4 ferrite nanoclusters of different sizes ranging from ∼30 to ∼120 nm. The nanoclusters synthesized via a hydrothermal polyol process show high crystallinity and a narrow size distribution. The magnetic properties of the nanoclusters demonstrate well-behaved magnetization and low-coercivity characteristics, ferrimagnetically at a large size, and superparamagnetically at a small size.

Manganese doped-iron oxide nanoparticle clusters and their potential as agents for magnetic resonance imaging and hyperthermia

“…From a structural point of view, the introduction of Mn determines a decrease in size of both the nanoclusters and the primary nanocrystals, which is reflected in the variations observed in saturation magnetisation: for lower doping regimes (0 o x o 0.5) the net magnetisation is increased due to the Mn contribution, while for higher doping regimes (x Z 0.5) the effects of size reduction prevail and cause its overall decrease. 28,32 Thus, our choice of introducing a low Mn doping content is intended as a conservative approach to boost the net magnetisation without heavily affecting the size of the nanocrystals and nanoclusters. In order to assess the effect of Mn-doping on our clusters, the DC magnetic susceptibility was measured as a function of temperature at low fields according to the ZFC-FC (Zero-Field Cooled-Field Cooled) protocols, while isothermal hysteresis loops were recorded at 5 K and body temperature (310 K).…”

“…Although the doping of the clusters can occur during an easy step of one-pot, rapid chemical synthesis, only few cases of relevant preliminary chemical studies have been reported so far. 28,29 In our experiments, Mn-doped iron oxide CNCs have been prepared and evaluated as MRI contrast agents as well as heating probes in magnetic fluid hyperthermia. These nanomaterials may hold a great potential for biomedical applications and highlight the need of more synthetic efforts to enrich the library of functional doped-CNCs.…”

Hyperthermia-induced in situ drug amorphization by superparamagnetic nanoparticles in oral dosage forms

“…25 The peak shift is accompanied with a lattice expansion (Table S1), indicating the successful incorporation of Zn 2+ and Mn 2+ ions into the γ-Fe2O3 crystal lattice. 23,35 Furthermore, no diffraction peaks corresponding to pure zinc oxide or manganese oxide were observed. The average crystallite size (dXRD) was about 14 nm for both γ-Fe2O3 and Zn0.5Fe2.5O4 and 18 nm for Mn0.5Fe2.5O4 (Figure 2a).…”

Synergistic Effect of Detection and Separation for Pathogen Using Magnetic Clusters

“…The magnetic saturation value is increased with increasing cluster size effects. 31 Both FT-IR and NMR spectra show that corresponding results of the modification of PCMNCs. The original form of polysorbate 80 contains a CO stretching vibration band at 1735 cm −1 , which is slightly shifted to 1733 cm −1 for the modified form; this is due to the presence of negatively charged tricarboxylate groups on the PCMNCs (Figure 2D).…”

“…The magnetic hysteresis loop of MNPs and PCMNCs were analyzed using a vibration sample magnetometer at 298 K. The magnetic saturation values at 15T are measured to be 67.7 and 68.3 emu g –1 for MNPs and PCMNCs, respectively (Figure S3). The magnetic saturation value is increased with increasing cluster size effects . Both FT-IR and NMR spectra show that corresponding results of the modification of PCMNCs.…”