Carboxymethylcellulose modified Fe3O4@SiO2@GdPO4:Tb3+,Ce3+ nanocomposites for combined optical and magnetic fluid hyperthermia in cancer therapy

Abstract

A stepwise synthetic method is reported for the synthesis of multifunctional, magnetic and luminescent composites with silica-coated Fe₃O₄ as the core and Ce³⁺ sensitized Tb³⁺ doped GdPO₄ embedded in carboxymethylcellulose. The phase composition, infrared spectra, luminescence and magnetic properties were characterized by X-ray diffraction, FTIR, photoluminescence spectroscopy and vibrating sample magnetometry, respectively. The synthesized materials exhibit high saturation magnetization and excellent luminescence properties. The composites show intense green emission at 545 nm upon excitation at 276 nm. They attain the hyperthermia temperature (∼42 °C) within the threshold alternating magnetic field (5 × 10⁶ kA m⁻¹ s⁻¹). The samples exhibit efficient induction heating properties which is highly desirable for magnetic hyperthermia application in cancer therapy. The materials are found to have excellent biocompatibility towards the MDA-231 breast cancer cell line and A549 lung cancer cell line with their in vitro cell viability showing 50% and 90%, respectively, for up to 200 μg mL⁻¹ concentration, and the IC₅₀ values reaching 154.33 ± 18.06 μg mL⁻¹ and 667.45 ± 20.03 μg mL⁻¹, respectively. The synthesized multifunctional magnetic luminescent nanocomposites provide a new insight for optical imaging and therapeutic agents for hyperthermia cancer therapy.