چكيده به لاتين
The development of nanoscience and application of magnetic nanoparticles due to their distinctive physical and chemical properties is currently a prominent subject in cancer diagnosis and treatment. Magnetic hyperthermia is used as an adjunct therapy to radiation therapy and chemotherapy; while in some cases can be utilized as a sole treatment method. Cancer tumor cells die at high temperatures in the range of 42-45° C. The combination of antibodies with the surface of the nanoparticles as carriers can deliver nanoparticles to the target tissue. In magnetic hyperthermia, following aggregation of nanoparticles in the tumor tissue, they can generate heat after receiving energy via a laser or an AC magnetic field. In this study, the treatment of brain tumors using magnetic hyperthermia with nanoparticles consisting of Fe3O4 core coated with gold and silver alloy as the first shell and two-dimensional transition metal dichalcogenides materials (TMDs) as the second shell is investigated. The optical properties of these particles inside the tumor, including the extinction coefficient and the Surface plasmon resonance (SPR) regarding the size and structure of nanoparticles, is evaluated to analyze the temperature distribution in the brain tissue. The results of this study indicate that Fe_3 O_4-〖Au〗_0.25 〖Ag〗_0.75@TMD composition with 1nm shell thickness of gold-silver alloy presents the optimal extinction coefficient and SPR in the biological window. Though gold-silver alloy can improve the extinction coefficient while preventing aggregation of nanoparticles; however their optical properties can’t occur in biological windows, so TMD materials have been adopted in this research, which can increase the extinction efficiency at higher wavelengths. The best extinction efficiency and SPR are observed for 〖WS〗_2 in the tumor; But 〖MoS〗_2 is suggested for further study due to its biocompatibility as well as with the acceptable extinction efficiency and SPR. Examination of the temperature distribution in the tumor using the proposed alloy composition indicates that after a short time of laser induction, the tumor temperature reaches 45 degrees; in which tumor core has the highest temperature, and it decreases radially. Magnetic hyperthermia enables deep tissues access to malignant brain tumors; which makes this method more efficient than the photothermal therapy.
