Preparation and characterization of structure-tailored magnetic fluorescent Fe₃O₄/P(GMA-EGDMA-NVCz) core-shell microspheres

Fe₃O₄ nanoparticles were prepared by solvothermal reaction, and structure-tailored Fe₃O₄/poly(glycidyl methacrylate-ethyleneglycol dimethacrylate-N-vinylcarbazole) (Fe ₃O₄/P(GMA-EGDMA-NVCz)) core-shell microspheres were achieved by distillation-precipitation polymerization of GMA, EGDMA, and NVCz in the presence of Fe₃O₄ nanoparticles. The properties of Fe₃O₄/P(GMA-EGDMA-NVCz) microspheres were characterized by transmission electron microscopy(TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), and fluorescence spectroscopy. The results showed that the size of Fe ₃O₄/P(GMA-EGDMA-NVCz) core-shell microspheres could be controlled to 930-470 nm by adjusting the amount of shell monomers, corresponding magnetic content of 45-82 wt%, and saturation magnetization of 32-63 emu/g. Moreover, the intensity of the fluorescence increased considerably with the decrease of shell thickness and the increase of NVCz concentration in the monomer mixture.