Iron–gold alloy nanoparticles serve as a cornerstone in hyperthermia-mediated controlled drug release for cancer therapy

Abstract

IntroductionThe efficacy of a chemotherapy drug in cancer therapy is highly determined by the ability to control the rate and extent of its release in vivo. However, the lack of techniques to accurately control drug release drastically limits the potency of a chemotherapy drug.Materials and methodsHere, we present a novel strategy to precisely monitor drug release under magnetic stimulation. Methotrexate (MTX), an anticancer drug, was covalently functionalized onto iron–gold alloy magnetic nanoparticles (Fe–Au alloy nanoparticles or NFAs) through 2-aminoethanethiol grafting and the ability of this drug–nanoparticle conjugate (NFA–MTX) in limiting HepG2 (liver carcinoma) cell growth was studied. Well-dispersed NFAs were prepared through pyrolysis.Results and discussionTransmission electron microscopy revealed the average nanoparticle size to be 7.22±2.6 nm, while X-ray diffraction showed distinct 2θ peaks for iron and gold, confirming the presence of iron and gold nanoparticles. Inductively coupled plasma mass spectrometry revealed that the amount of NFA–MTX conjugate ingested by HepG2 cancer cells was 1.5 times higher than that ingested by L929 fibroblasts, thereby proving a higher selective ingestion by cancer cells compared to normal cells. Fourier-transform infrared spectroscopy revealed the breakage of Au-S bonds by the heat generated under magnetic field stimulation to release MTX from the NFA–MTX conjugate, triggering a 95% decrease in cellular viability at 100 µg/mL.ConclusionThe ability of NFA–MTX to dissociate under the influence of an applied magnetic field provides a new strategy to induce cancer cell death via hyperthermia. Applications in drug delivery, drug development, and cancer research are expected.

Hyperthermia-Induced Controlled Local Anesthesia Administration Using Gelatin-Coated Iron–Gold Alloy Nanoparticles

“…The presence of Fe and Au in FeAu Nps was further confirmed through XRD, which showed distinct 2 θ peaks at 38.6, 44.8, and 64.4° that correspond to the (111), (200), and (220) planes of face center cubic (FCC) of gold and the 2 θ peaks at 43.9 and 64.8 that correspond to the (110) and (200) planes of body-centered cubic (BCC) in iron, thereby further confirming the presence of Fe and Au in FeAu Nps ( Figure 1 d). These results were firmly consistent with our previous study as well as with those of Krishnamurthy et al [ 21 , 28 ], thereby confirming the formation of FeAu Nps.…”

“…However, as the nanoparticles are not coated with any biocompatible material, the cytotoxic effects of nanoparticles alone cannot be avoided. We have previously demonstrated that chemodrug release to target cancer cells is achievable using hyperthermia [ 21 ]. Further, we used the iron–gold core–shell nanoparticles toward Magnetic Resonance Imaging (MRI) and Optical coherence tomography (OCT) imaging using photostimulation, showing a multitude of nanoparticle properties that can be exploited in biomedicine.…”

Recent Advances in the Use of Iron–Gold Hybrid Nanoparticles for Biomedical Applications

“…This study reflects the successful report of iron–gold nanohybrids as a single system for multifunctional uses in cancer therapy [ 105 ]. In another example, Yun Quan-Li et al have covalently attached a cytotoxic agent such as methotrexate to iron–gold alloy NPs and reported that with the increase in the applied magnetic field, the release of methotrexate increased in an incremental manner [ 111 ].…”

Synthesis, Properties, and Biological Applications of Metallic Alloy Nanoparticles

“…Magnetic nanoparticles can be heated under the magnetic field leading to direct killing of cancer cells, or by releasing the carried drug to kill the cancer cells [ 265 , 266 ]. Many kinds of magnetic nanoparticles (superparamagnetic iron-oxide, Fe 3 O 4 or Fe 2 O 3 , Mn–Zn, and Fe–Au nanoparticles) are created and surface-modified using aminosilane, antibodies, PEG-phospholipids, or cyclic tripeptide of arginine-glycine-aspartic acid for the treatment of glioblastoma multiforme tumors [ 267 , 268 , 269 , 270 , 271 ]; or in the activation of reactive oxygen species via the p53 pathway in killing HepG2 human hepatocellular carcinoma and A549 human lung adenocarcinoma cells [ 272 ].…”