Doxorubicin-Loaded Thermoresponsive Superparamagnetic Nanocarriers for Controlled Drug Delivery and Magnetic Hyperthermia Applications

Abstract

This study reports on the development of thermoresponsive core/shell magnetic nanoparticles (MNPs) based on an iron oxide core and a thermoresponsive copolymer shell composed of 2-(2-methoxy)­ethyl methacrylate (MEO2MA) and oligo­(ethylene glycol)­methacrylate (OEGMA) moieties. These smart nano-objects combine the magnetic properties of the core and the drug carrier properties of the polymeric shell. Loading the anticancer drug doxorubicin (DOX) in the thermoresponsive MNPs via supramolecular interactions provides advanced features to the delivery of DOX with spatial and temporal controls. The so coated iron oxide MNPs exhibit superparamagnetic behavior with a saturation magnetization of around 30 emu g–1. Drug release experiments confirmed that only a small amount of DOX was released at room temperature, while almost 100% drug release was achieved after 52 h at 42 °C with Fe3−δO4@P­(MEO2MA60OEGMA40), which grafted polymer chains displaying a low critical solution temperature of 41 °C. Moreover, the MNPs exhibit magnetic hyperthermia properties as shown by specific absorption rate measurements. Finally, the cytotoxicity of the core/shell MNPs toward human ovary cancer SKOV-3 cells was tested. The results showed that the polymer-capped MNPs exhibited almost no toxicity at concentrations up to 12 μg mL–1, whereas when loaded with DOX, an increase in cytotoxicity and a decrease of SKOV-3 cell viability were observed. From these results, we conclude that these smart superparamagnetic nanocarriers with stealth properties are able to deliver drugs to tumor and are promising for applications in multimodal cancer therapy.

Synthesis, Principles, and Properties of Magnetite Nanoparticles for In Vivo Imaging Applications—A Review

“…In addition, the theragnostic approach also includes using the SPIONs properties to destroy proliferating cells, by hyperthermia-mediated drug delivery [112], or in combination with optical probes able induce photothermal effects when combined with heptamethine cyanine [109], treating tumors in mice by photodynamic therapy using Chlorine e6 or Dextran Benzoporphyrin coating SPIONs, reported in [113] and [114], respectively.…”

Smart materials for drug delivery and cancer therapy

“…For example, Liu et al employed SPIONs to accurately delivery DOX‐loaded MSNs to tumor site with minimal toxicity to healthy tissues in the guidance of magnetic field (Figure 12A). 270 Besides, a SPIONs‐based core‐shell nanostructure loading DOX into the thermoresponsive copolymer shell was successfully established 271 . They found that the DOX cumulative release percent from this nanostructure incubated at 37°C was almost 0% after 10 h, while the release amount encouragingly reached to 100% at 42°C after 54 h. It is interesting to note that the increased temperature of SPIONs, possessing magnetic hyperthermia effect, was high enough (>42°C) to initial burst release of DOX under magnetic stimulation.…”

Recent Advances of Magnetic Nanomaterials in Bone Tissue Repair

“…Antibiotics, growth factors, and microRNA and siRNA related to osteogenesis can improve the repair effect of bone defects (Jia et al, 2018 ; Li et al, 2018 ; Ferjaoui et al, 2019 ). However, these drugs cannot target specific sites or produce a direct repair effect.…”