چكيده به لاتين
Recent advances, have suggested thermal methods to effectively cure cancers. These methods have the ability to kill cancer cells by providing enough heat to the destructive tissue and also protect healthy tissue. Biological effects of thermal stimulation have created types of clinical applications in cancer treatment. Researchers, have discovered countless heat transfer methods, including photothermal therapy to deliver heat to a specific area, such as a tumor. The advent of nanotechnology, has introduced the nanostructures as the front line of cancer. These nanostructures have many applications in diagnosis and treatment of diseases, especially cancer, including the factors that produce and retain heat in photothermal therapies. Photothermal therapy using plasmonic nanoparticles is called “plasmonic photothermal “. In this treatment modality near-infrared spectrum that is produced by Nd:YAG and diode lasers, is used because of its quick absorbance through tissue. Generally, the temperature distribution and amount of damage caused by the laser, depend on the properties of the treated tissue, the nanoparticle and the method used. In this research, treatment of human liver cancer by plasmonic photothermal therapy using the core (SiO2)-shell (Au/Ag) nanoparticles will be studied. Also, nanoparticles size and morphology will be evaluated on optical properties of them inside the tissue such as extinction and scattering coefficients and surface plasmon resonance, for investigating temperature distribution in the target tissue. The results of the study indicate that nanoshells consisting of a core with a radius of 15 nm and a shell (gold) with a radius of 20 nm have the best extinction coefficients and surface plasmon resonance in the therapeutic window. Examination of the temperature distribution in the tumor using the optimal nanoshell indicates that, tumor temperature reaches the desired temperature of 45 ℃ shortly after the onset of laser irradiation. Also, the temperature distribution in the tumor decreases radially from the center to outside. Photothermal therapy is an adjunctive therapy and sometimes the only treatment, with access to deep tissue, reduces the possible damage to healthy tissue and has a more favorable outcome in the definitive treatment of cancerous tumors.
