The influence of coating on the structural, magnetic and colloidal properties of LSMO manganite and the heating mechanism for magnetic fluid hyperthermia application

Abstract

Combustion synthesized superparamagnetic La_0.7Sr_0.3MnO₃ nanoparticles have been studied for magnetic fluid hyperthermia applications. The effect of the coating concentration of acrypol on the colloidal, magnetic and heating properties of L_0.7Sr_0.3MnO₃ have been studied. Uncoated and acrypol coated samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, high resolution transmission electron microscopy and vibrating sample magnetometer studies. The power absorbed by acrypol coated nanoparticles suspended in phosphate buffer solution from a 265 kHz radio frequency field was measured as a function of coating concentration and field amplitude H. For H = 40.4 kA m⁻¹ the maximum specific absorption rate was 80.82 W g⁻¹ for 4% coating concentration. All results evidenced that among all the coated samples, 2, 4, 6 and 8% coating concentrations, the sample with 4% coating concentration shows the highest induced heating temperature, the highest specific absorption rate and the highest biocompatibility.