Multifunctional Fluorescence/Magnetic Composite Microspheres for Cell Tracking and Drug Targeting Usage

A supermagnetic iron oxide (SPIO) microspheres is emerging as an ideal tool for cell tracking and drug targeting delivery. However, its low intracellular labeling efficiency has limited the potential usage. We have developed CdTe-incorporated CMCH/SiO₂-coated core-shell composite microspheres, Fe₃O₄@SiO₂@CMCH/CdTe (FSCC), with diameters of 210 nm, as a multifunctional magnetic vector that can efficiently orient targeted cells and visualize easily by UV. The multifunctional nanoparticles were injected into nude mice, and the potential usage as a dual modality imaging agent in vivo was demonstrated by MRI and UV light.