Synthesis of amine-polyglycidol functionalised Fe3O4@SiO2 nanocomposites for magnetic hyperthermia, pH-responsive drug delivery, and bioimaging applications

Abstract

The combined chemotherapy and thermal therapy is mainly considered in clinical applications in cancer therapy. However, the preparation of multifunctional nanomaterials is an attractive approach for cancer treatment. In this report, we present the synthesis of amine-polyglycidol functional shell modified-silica coated-magnetic iron oxide nanocomposites (Fe₃O₄@SiO₂@APG-F) for a FITC conjugated drug carrier system and/or hyperthermia agent in cancer therapy. The Fe₃O₄@SiO₂@APG-F nanocomposite exhibits superparamagnetic properties with a magnetic saturation value of approximately 17.2 emu g⁻¹. The magnetic hyperthermia experiment shows a very fast temperature increase within a short time (45 °C in 4.5 min) when applying an alternating magnetic field (AMF), which is considered to be an appropriate temperature for the localized hyperthermia treatment in cancer therapy. Further, the fluorescein isothiocyanate (FITC), a model fluoropore, was conjugated with the terminal amine groups of the Fe₃O₄@SiO₂@APG to endow the green fluorescent behavior that may be desirable for biological imaging applications. The Fe₃O₄@SiO₂@APG-F material shows high drug loading efficiency and the MTT assay results evidenced that the synthesised Fe₃O₄@SiO₂@APG-F nanocomposites are biocompatible. The fluorescence microscopic images show the particles can be effectively taken up by cancer cells. Therefore, the FITC conjugated Fe₃O₄@SiO₂@APG-F nanocomposites that possess a magnetic core covered by silica coating, organic APG functional shell, and FITC fluorophore together in a single entity could serve as a good hyperthermia agent, drug delivery carrier, and fluorescent contrast agent for bioimaging. Thus, the Fe₃O₄@SiO₂@APG-F nanocomposite could be considered as a promising material to be used in multimodal cancer therapy.