(694c) Continuous Separation of Magnetic Nanoparticles to Enhance Size and Surface Homogeneity

Magnetic nanoparticle has foreseeable potential in biomedical applications. Due to the size and magnetic property, nanoparticle is able to access anywhere in the human body. This creates a great interest in pharmaceutical and engineering researches, including drug delivery, hyperthermia, and other in vivo applications. However, because of the small size of the magnetic nanoparticle, it limits the control the particle properties, such as size, surface property, composition and shape. Unfortunately, most of the known separation techniques are not applicable at the nanoscale. This research suggests a separation process to separation magnetic nanoparticle with different size and surface properties. A mixture of poly-disperse and PEGylated superparamagnetic iron oxide nanoparticles (SPION) is immobilized inside an external magnetic field. The field is provided by a series of computer controlled electromagnetic coils. SPION can be separated into multiple narrow distributions by size or surface property in accordance with the control in field strength and frequency. The size of the SPION particle is proportional to its iron content, which also determines its response to magnetic fields. By manipulating the field strength, different SPION size distributions can be separated. The size distribution is quantified by dynamic light scattering, and surface homogeneity is reported by its zeta potential.