Magnetic fluid hyperthermia (MFH) offers a means of doing this, which involves direct intratumoral injection of magnetic fluids into the target region, and then the particles are selectively heated in an externally applied alternating magnetic field (AMF). The technique uses the Curie temperature (Tc) of the magnetic material in magnetic response heating to achieve automatic temperature control and a constant temperature. Thus this technique could avoid overheating of the tissue. In vitro and in vivo experiments with magnetic fluids have documented significant antitumor effects in a murine model of liver cancer . Heat also enhances the effectiveness of radiotherapy and magnifies the cytotoxicity of many anticancer drugs.
For this reason, hyperthermic treatment, alone or in combination with traditional anticancer treatments, is receiving a great deal of attention.Arsenic trioxide (As2O3), a kind of Traditional Chinese Medicine, has drawn researchers�� great interest due to its high efficacy in the treatment of acute promyelocytic leukaemia (APL). It also has been tested in some solid cancers, such as hepatocellular carcinoma , gastric carcinoma , breast cancer , etc. After intravenous or oral administration , As2O3 has been accompanied a series of side effects, such as skin reactions, gastrointestinal upset, hepatitis and even cardiotoxicity . To make the best use of the drug and reduce the harmfulness to the body, it is very important to find a new form of As2O3 for clinical therapy.
In this study, As2O3 was integrated with Mn0.5Zn0.
5Fe2O4 nanoparticles, which have super-paramagnetic Batimastat characteristics. This feature is quite suitable for use in hyperthermia. On the one hand, a certain concentration of magnetic nanoparticles could absorb high power and transform it into heat in an alternating magnetic field, while barely damaging peripheric tissue. If used in vivo, the magnetic nanoparticles could be inducted in the target region by an external magnetic field. In this way, not only does the drug level in the tumor region rise, but also the drug dose decreases. Finally the nanosized As2O3/Mn0.5Zn0.
5Fe2O4 complex could Dacomitinib produce chemotherapy and thermotherapy effects at the same time.2.?Results and Discussion2.1. Characteristics of Mn0.5Zn0.5Fe2O4 NanoparticlesFigure 1a shows an image of Mn0.5Zn0.5Fe2O4 nanoparticles acquired by TEM. It shows that they were nearly spherical, with high electron-density and uniform in size. The X-ray diffraction pattern of the ferrite sample is shown in Figure 1b. The observed diffraction lines were found to correspond to those of a standard manganese ferrite pattern, thereby indicating that the samples have spinel structure.