Improving the homogeneity of superparamagnetic nanoparticles and a study of their physicochemical properties

Abstract

Superparamagnetic iron oxide nanoparticles (SPIONs) have enormous potential in biomedical applications, including drug delivery, hyperthermia, and magnetic resonance imaging. However, the broad size distribution of SPIONs hinders translation from research results to clinical trials due to safety concerns and performance variabilities. Conventional size selection techniques fail to provide monodisperse SPIONs in comparison with other nanomaterials such as gold, silica, and other nanoparticles. Therefore, a new size fractionation method, diffusive magnetic fractionation (DMF), was introduced to solve current issues. The DMF separated different sized SPIONs by utilizing their mobility differences, which repeatedly released and attracted SPIONSs via a periodic magnetic field. The DMF performances showed independency from 5 different scaling conditions and less than 5% lost during the separation. The DMF separated SPIONs (DMF-SPIONs) showed much narrower in size distribution than conventional methods. In summary, the DMF was proved to be an efficient, scalable and controllable high performance separation method.