Controlled Synthesis and Characterization of Micrometric Single Crystalline Magnetite With Superparamagnetic Behavior and Cytocompatibility/Cytotoxicity Assessments

Abstract

A new class of magnetite (Fe 3 O 4) particles, coined as "Single Crystalline Micrometric Iron Oxide Particles" (SCMIOPs), were obtained by hydrothermal synthesis. Both the single Fe 3 O 4 phase content and the particle sizes range, from 1 µm to 30 µm, can be controlled by synthesis. The notable finding states that these particles exhibit vanishing remanent magnetization (sr=0.28 emu/g) and coercive force (Hc=1.5 Oe), which indicate a superparamagnetic-like behavior (unexpected at micrometric particles size), and remarkably high saturation magnetization (ss=95.5 emu/g), what ensures strong magnetic response, and the lack of agglomeration after the magnetic field removal. These qualities make such particles candidates for biomedical applications, to be used instead of magnetic nanoparticles which inevitably involve some drawbacks like aglommeration and insufficient magnetic response. In this sense, cytocompatibility/ cytotoxicity tests were performed on human cells, and the results have clearly indicated that SCMIOPs are cytocompatible for healthy cell lines HaCaT (human keratinocytes) and HEMa (primary epidermal melanocytes) and cytotoxic for neoplastic cell lines A375 (human melanoma) and B164A5 (murine melanoma) in a dose-dependent manner.

Biocompatible Magnetic Colloidal Suspension Used as a Tool for Localized Hyperthermia in Human Breast Adenocarcinoma Cells: Physicochemical Analysis and Complex In Vitro Biological Profile

“…Our research group has already demonstrated that Fe 3 O 4 nanoparticles are responsible for inducing alterations of amelanotic human A375 cells and murine melanoma B164A5 cells depending on cell phenotype and metastatic activity [ 71 , 72 , 73 ]. However, through the current study, antitumorigenic screening of these nanoparticles extends to breast adenocarcinoma cells, and based on the present data, MCS developed in this study revealed promising potential as a hyperthermia-inducing tool in the biological environment.…”

<p>Thermosensitive Betulinic Acid-Loaded Magnetoliposomes: A Promising Antitumor Potential for Highly Aggressive Human Breast Adenocarcinoma Cells Under Hyperthermic Conditions</p>

“…Our group already reported that MIONPs are cytotoxic against tumor melanoma cells, generating different responses depending on the cell origin, phenotype and metastatic potential. [72][73][74] The stronger BA cytotoxic effect on MDA-MB-231 cells versus MCF7 cells could explain the difference in cell viability percentages induced by the BA-loaded nanoplatforms when applied on the two breast adenocarcinoma cell lines. In terms of hyperthermia effects, it could be noticed a decrease in the MDA-MB -231 cell population when treated with BA-loaded nanoformulations, compared to the same treatment groups under normothermic conditions.…”

Assessment of Betulinic Acid Cytotoxicity and Mitochondrial Metabolism Impairment in a Human Melanoma Cell Line

“…MTT assay. Cell viability was evaluated by using the MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) kit (Roche, Mannheim, Germany) according to the experimental protocol described in our previous studies [ 59 ]. In brief, HaCaT and A375 cells (1 × 10 4 /200 μL medium/well) were seeded in 96-well plates and stimulated with increasing concentrations (0–50 µM) of BA solubilized in DMSO for 24 h. The plates were incubated for 3 h at 37 °C with 10 µL/well of MTT reagent, followed by addition of buffer solution (100 µL/well) and incubation at room temperature and dark for 30 min.…”