Evaluating magnetic and thermal effects of various Polymerylated magnetic iron oxide nanoparticles for combined chemo-hyperthermia

Abstract

Assessing the heat-generation from magnetic iron oxide nanoparticles (MNPs) under magnetic excitation for hyperthermia applications is highly demanded. We, herein, report the preparation of different Polymerylated MNPs (PMNPs) capped with five widely used polymers (PVP, PEG, Dextran, HA, and PAA) based on our Ko-precipitation Hydrolytic Basic (KHB) methodology. The physiochemical and magnetic properties of PMNPs were fully characterized using various spectroscopic techniques including TEM, DLS, FTIR, TGA, XRD, and VSM. PMNPs exhibited controllable small sizes (5–15 nm), high saturation magnetizations (M_s = 49–72 emu g⁻¹), superparamagnetic behavior, stable aqueous dispersions, and excellent biocompatibilities. The thermal effects of the various PMNPs in response to an alternating magnetic field (AMF) were mapped showing high heating efficiencies with distinctive heating responses (specific absorption rate, SAR = 40–160 W g⁻¹). Remarkably, PVP–MNPs displayed superior heat induction power compared to other PMNPs rapidly reaching hyperthermia temperatures of 42 °C in only 90 s, and 45 °C in 120 s. Finally, synergetic chemo-hyperthermal anticancer effects of drug-loaded PMNPs against metastatic MDA-MB-231 breast cancer cells, in the presence and absence of AMF, were demonstrated. It was found that the Dox@PVP-MNP under AMF was the most effective, killing almost all the tested cancer cells in relatively short times (only 15 minutes of magnetic excitation), low doses (0.5–1 mg), and clinically-relevant AC magnetic fields (H₀ = 170 Oe and frequency = 332.8 kHz). These findings strongly suggest that the PVP-MNP formulation holds great promise for combined magnetically-triggered drug delivery and hyperthermia, and will be worth investigating for further in vivo potential.