Potassium Ferrite for Biomedical Applications

Abstract

Ferrites have been widely studied for their use in the biomedical area, mostly due to their magnetic properties, which gives them the potential to be used in diagnostics, drug delivery, and in treatment with magnetic hyperthermia, for example. In this work, KFeO2 particles were synthesized with a proteic sol-gel method using powdered coconut water as a precursor; this method is based on the principles of green chemistry. To improve its properties, the base powder obtained was subjected to multiple heat treatments at temperatures between 350 and 1300 °C. The samples obtained underwent structural, morphological, biocompatibility, and magnetic characterization. The results show that upon raising the heat treatment temperature, not only is the wanted phase detected, but also the secondary phases. To overcome these secondary phases, several different heat treatments were carried out. Using scanning electron microscopy, grains in the micrometric range were observed. Saturation magnetizations between 15.5 and 24.1 emu/g were observed for the samples containing KFeO2 with an applied field of 50 kOe at 300 K. From cellular compatibility (cytotoxicity) assays, for concentrations up to 5 mg/mL, only the samples treated at 350 °C were cytotoxic. However, the samples containing KFeO2, while being biocompatible, had low specific absorption rates (1.55–5.76 W/g).

Unveiling the Synthesis of Strontium Ferrites by Sol-Gel and Laser Floating Zone Methods for Energy Application

“…Figure 2 shows three distinct regions of mass loss. The first region is found between 50 and 400 • C, where a loss of 15% occurs due to the nitrate's elimination present in the sample [27]. A second region from 400 to 700 • C, where a possible mass loss of 20% is observed due to the evaporation of organics [28], accompanied by an exothermic peak in the DTA curve, which may be associated with the formation of a crystalline phase, at a temperature of approximately 650 • C. Between 750 and 850 • C there is a mass gain of 3% followed by a new exothermic peak at 750 • C. Finally, between 900 and 1200 • C, there is a new mass loss of 2%.…”

Cobalt Ferrite Synthesized Using a Biogenic Sol–Gel Method for Biomedical Applications

“…Consisting of a rich composition of sugar, amino acids, and minerals, this compound acts as a surfactant for the reaction [5,20]. This approach has been employed previously for the synthesis of nanoparticles such as BaFe 12 O 19 [21], SrFe 12 O 19 [22], KfeO 2 [23], and SrAl 2 O 4 [24].…”