Preparation and characterization of 5-fluorouracil surface-imprinted thermosensitive magnetic microspheres

5-Fluorouracil surface-imprinted thermosensitive magnetic microspheres were prepared by using Fe 3 O 4 -encapsulating carbon microspheres as cores, N -isopropylacrylamide as thermosentitive monomer, ammonium persulfate as initiator, N , N ′-methylenebisacrylamide as crosslinker, and 5-fluorouracil as template molecule. The formation of these hybrid microspheres was verified by field emission scanning electron microscopy, transmission electron microscopy, Fourier transformation infrared spectroscopy, thermogravimetry, and dynamic light scattering. The results of the latter measurements show that the as-synthesized microspheres have a hydrodynamic diameter of 326 nm with the lower critical solution temperature of around 43 °C. The obtained microspheres are magnetic and show good potential for controlled loading and release of 5-fluorouracil. Graphical abstract