Polymer modified magnetic-luminescent nanocomposites for combined optical imaging and magnetic fluid hyperthermia in cancer therapy: analysis of Mn2+ doping for enhanced heating effect, hemocompatibility and biocompatibility

Abstract

Magnetic Mn_xFe_3−xO₄ nanoparticles and polymer coated magnetic-luminescent Mn_xFe_3−xO₄@(Y,Dy/Eu)VO₄ nanocomposites were prepared to study their comparative heat generation efficiency and biocompatibilities. Cubic crystalline phases were obtained for the nanoparticles and cubic–tetragonal biphasic phases were observed for the nanocomposites. The successful doping of Mn²⁺ was also confirmed by inductively coupled plasma optical emission spectroscopy. The compositions and the surface modification chemistry were confirmed by infrared spectroscopy. The formation of near-spherical and cubic/cuboid nanoparticles was observed from electron microscopy. Comparative analysis of induction heating efficiencies and magnetization values of the synthesized materials was performed for the samples. The samples showed an efficient heating effect under the influence of alternating magnetic field strengths – 3.05 × 10⁶ kA m⁻¹ s⁻¹ and 4.58 × 10⁶ kA m⁻¹ s⁻¹. A higher Mn²⁺ content was found to possess higher magnetization and perform better in heat generation. The nanocomposites give brilliant color emission on excitation using ultraviolet wavelengths – 300 and 315 nm. Their hydrodynamic radii and zeta potential values indicate good stability of the dispersions. Hemocompatibility studies were carried out to ascertain the effect on red blood cells. The materials were also found to exhibit excellent biocompatibility towards HeLa cell lines. This article will provide a new insight into the use of Mn_xFe_3−xO₄ based nanocomposites for magnetic fluid hyperthermia in cancer therapy.