Cluster/shell citrate-Fe3O4/chitosan nanoparticles for enhancing heating efficiency in combined magnetic and photothermal therapy

Abstract

Antitumor hyperthermia therapy is an emerging approach for the thermal treatment of cancer. Magnetite-based nanoparticles are very promising hyperthermia agents due to its biocompatibility and versatile application. In this study, engineered citrate functionalized magnetite nanoparticles resulted in an adequate colloid for the desire application: 12.57 nm ± 3.86, −44.5 ± 0.6 mV, hydrophilic character, and 85.2 ± 1.6 emu/g. Those citrate-functionalized magnetite colloids were embedded into a chitosan nanomatrix to obtain cluster/shell citrate-magnetite/chitosan nanoparticles with demonstrated short-term stability. In addition, freeze-drying using saccharose as cryoprotectant was used for a long-term preservation. Cluster/shell nanostructure was confirmed using Fourier transform infrared spectroscopy, X-ray diffraction analysis, thermogravimetric analysis, surface electrokinetics and thermodynamics, dynamic light scattering and high resolution transmission electron microscopy. Citrate-magnetite/chitosan nanoparticles demonstrated negligible cytotoxicity in a non-tumor cell line and adequate characteristics for parenteral administration (187.33 ± 54.85 nm and haemocompatibility). Magnetic behaviour was not affected by the chitosan shell onto the citrate-magnetite cluster of particles. Thermal enhance capacity was fully investigated using magnetic hyperthermia and photothermal modalities. Specific absorption rate values resulted for citrate-magnetite/chitosan NPs were superior to that obtained for single core particles in magnetic hyperthermia (393 ± 45 and 239 ± 31) and photothermal therapy (384 ± 7.1 and 272 ± 0.8, respectively). Therefore, citrate-magnetite/chitosan cluster/shell nanoparticles could find antitumor hyperthermia applications by using a systemic a dual magneto-photo-thermal therapy.