AC and DC magnetic softness enhanced dual-doped γ-Fe2O3 nanoparticles for highly efficient cancer theranostics

Abstract

Theranostics " by magnetic nanofluid hyperthermia (MNFH) combined with T-2-weighted MR contrast imaging (MRI) using superparamagnetic nanoparticles (SPNPs) has been drawn a huge attraction in nanomedicine. However, insufficient AC heating power at the biologically safe range of AC magnetic field (H-AC) (H-appl < 190 Oe, f(appl) < 120 kHz) and unsatisfactorily low r(2)-relaxivity keep SPNPs challenging for cancer theranostics agent applications. Here, innovatively designed and developed AC and DC magnetic softness enhanced dual-doped (Ni0.6Zn0.4)-gamma Fe2O3 (MSE gamma-IO) SPNPs with significantly enhanced both intrinsic loss power (ILP, ~ 4.0 nH m(2) kg(-1)) at the H-appl.f(appl) = 1.23x10(9) A m(-1) s(-1) and r(2)-relaxivity (r(2) = 660.4 mM(-1) s(-1)) are reported. The significantly enhanced ILP, and r(2)-relaxivity of dual-doped MSE gamma-IO SPNPs were primarily attributed to the distinctly enhanced AC magnetic softness directly related to the HAC absorption and fappl resonance efficiency, and the DC magnetic softness dominantly controlled by the occupation and spatial distribution of Ni2+ in O-h vacancies sites, and Zn2+ cations in T-d sites of gamma-Fe2O3, respectively. The biocompatibility and bioavailability experimentally evaluated by in-vitro and in-vivo studies demonstrated that the dual-doped MSE gamma-IO SPNPs can be a promising candidate for highly efficient cancer theranostics agent for future nanomedicine.