Synthesis and characterisation of doxorubicin-loaded functionalised cobalt ferrite nanoparticles and their in vitro anti-tumour activity under an AC-magnetic field

Abstract

Purpose: To synthesise and evaluate the anti-tumour properties of doxorubicin-loaded xanthan gumfunctionalised cobalt ferrite nanoparticles (CoFe2O4.NPs@XG-Doxo) under an AC-magnetic field. Methods: Multidimensional magnetic cobalt ferrite (CoFe2O4) nanoparticles (NPs) were synthesised by a co-precipitation method. The synthesised cobalt ferrite nanoparticles (CFNPs) were functionalised with xanthine gum (XG) and subsequently characterised by Fourier transform-infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and contact angle studies. Vibrating sample magnetometry (VSM) was used for magnetic measurements of the native and XG-coated CFNPs. The microstructural morphology of the uncoated and XG-coated CFNPs was established using scanning electron microscopy (SEM), atomic force microscopy (AFM) and dynamic light scattering (DLS) studies. Finally, the doxorubicin release profile of the drug-loaded functionalised CFNPs was evaluated using an oscillating magnetic field (OMF) apparatus in the presence of an externally applied magnetic field. Results: XG coating decreased the contact angle of the native CFNPs from 92° to 40°, which indicates that it modified the CFNP surface from hydrophobic to hydrophilic. VSM analysis demonstrated that CoFe2O4.NPs@XG also retained the magnetic characteristics of the bare cobalt ferrite nanocrystals, endorsing its application as a promising magnetic nanovector (MNV). The synthesised CoFe2O4.NPs@XG-Doxo exhibited significantly higher controlled discharge of doxorubicin at acidic pH (5.0) than at neutral pH (7.4). In vitro analysis revealed the remarkable lower systematic toxicity of XGcoated CoFe2O4.NPs compared with uncoated CFNPs against Chinese hamster ovary (CHO) and Huh7 cell lines. Conclusion: These results indicate that XG-coated CFNPs are a biocompatible MNV for doxorubicin.