Magnetometric Measurements of Low Concentration of Coated Fe_{3}O_{4} Nanoparticles

A modi ed RF SQUID system with the 2 order gradiometer has been tested for the purposes of detecting the magnetic nanoparticles as potential carriers of biological medicament. The paper presents basic information about the sensitivity of the system and its use for quanti cation of low concentration of coated Fe3O4 magnetic nanoparticles. Model measurements provided information that enabled us to de ne the parameter in uencing the experimental results. The volume of the biological object and its distance from the antenna appear to have the signi cant in uence on the measurement accuracy.