Synthesis, Characterization and Magnetic Hyperthermia of Monodispersed Cobalt Ferrite Nanoparticles for Cancer Therapeutics.

Mauricio A Medina,José Tapia Ramírez,R Antaño-López,L G Arriaga,A Ángeles-Pascual,Edilso Reguera,A Vera,Goldie Oza,L Leija,José Manuel Hernández Hernández,Marlene González M

doi:10.3390/molecules25194428

Abstract

Magnetic nanoparticles such as cobalt ferrite are investigated under clinical hyperthermia conditions for the treatment of cancer. Cobalt ferrite nanoparticles (CFNPs) synthesized by the thermal decomposition method, using nonionic surfactant Triton-X100, possess hydrophilic polyethylene oxide chains acting as reducing agents for the cobalt and iron precursors. The monodispersed nanoparticles were of 10 nm size, as confirmed by high-resolution transmission electron microscopy (HR-TEM). The X-ray diffraction patterns of CFNPs prove the existence of cubic spinel cobalt ferrites. Cs-corrected scanning transmission electron microscopy–high-angle annular dark-field imaging (STEM–HAADF) of CFNPs confirmed their multi-twinned crystallinity due to the presence of atomic columns and defects in the nanostructure. Magnetic measurements proved that the CFNPs possess reduced remnant magnetization (MR/MS) (0.86), which justifies cubic anisotropy in the system. Microwave-based hyperthermia studies performed at 2.45 GHz under clinical conditions in physiological saline increased the temperature of the CFNP samples due to the transformation of radiation energy to heat. The specific absorption rate of CFNPs in physiological saline was 68.28 W/g. Furthermore, when triple-negative breast cancer cells (TNBC) in the presence of increasing CFNP concentration (5 mg/mL to 40 mg/mL) were exposed to microwaves, the cell cytotoxicity was enhanced compared to CFNPs alone.

Highlights

Magnetic nanoparticles (MNPs) are attracting much scientific attention due to their application in the fields of theranostic imaging, cell tracking, MRI, hyperthermia, drug delivery, giant magnetoresistance-based biosensors, and the separation of biomolecules such as DNA and proteins [1,2,3,4].Uniquely, MNPs possess inverse spinel structures in the form of MFe2 O4, where M corresponds toCo+2, Fe+2, Ni+2, Mn+2, etc., and inhabits either tetrahedral or octahedral interstitial sites
There are many reaction parameters that play an important role in the successful synthesis and stabilization of the NPs such as the length of the reflux time, temperature, type of surfactant, type of solvent, the gas in which the reaction is performed, and concentration of the precursors
The size and shape of the nanoparticles are determined by the reflux temperature, time, the type of surfactant and solvent [37]

Summary

Introduction

Magnetic nanoparticles (MNPs) are attracting much scientific attention due to their application in the fields of theranostic imaging, cell tracking, MRI, hyperthermia, drug delivery, giant magnetoresistance-based biosensors, and the separation of biomolecules such as DNA and proteins [1,2,3,4].Uniquely, MNPs possess inverse spinel structures in the form of MFe2 O4 , where M corresponds toCo+2 , Fe+2 , Ni+2 , Mn+2 , etc., and inhabits either tetrahedral or octahedral interstitial sites. Magnetic nanoparticles (MNPs) are attracting much scientific attention due to their application in the fields of theranostic imaging, cell tracking, MRI, hyperthermia, drug delivery, giant magnetoresistance-based biosensors, and the separation of biomolecules such as DNA and proteins [1,2,3,4]. MNPs exhibit relaxation, which can occur via two mechanisms: Brownian (relaxation time in which the magnetic dipole rotates in the form of a rigid body and is completely locked inside the particle) or Neel relaxation (switching of the magnetic dipole between two easy axes with respect to time). MNPs under an alternating current (AC) magnetic field exhibit heating effects due to the losses when there is a reversal of magnetization taking place in the magnetic nanoparticles [12,13,14]

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Results

Conclusion