Intelligent inorganic nanoparticles were designed and produced for use in imaging and annihilating tumour cells by radio-frequency (RF) hyperthermia. Nanoparticles synthesised to provide RF hyperthermia must have magnetite properties. For this purpose, magnetite nanoparticles were first synthesised by the coprecipitation method (10-15 NM). These superparamagnetic nanoparticles were then covered with gold ions without losing their magnetic properties. In this step, gold ions are reduced around the magnetite nanoparticles. Surface modification of the gold-coated magnetic nanoparticles was performed in the next step. A self-assembled monolayer was created using cysteamine (2-aminoethanethiol) molecules, which have two different end groups (SH and NH2). These molecules react with the gold surface by SH groups. The NH2 groups give a positive charge to the nanoparticles. After that, a monoclonal antibody (Monoclonal Anti-N-CAM Clone NCAM-OB11) was immobilised by the 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxysuccinimide method. Then, the antenna RF system (144.00015 MHz) was created for RF hyperthermia. The antibody-nanoparticle binding rate and cytotoxicity tests were followed by in vitro and in vivo experiments. As the main result, antibody-bound gold-coated magnetic nanoparticles were successfully connected to tumour cells. After RF hyperthermia, the tumour size decreased owing to apoptosis and necrosis of tumour cells.