Fe3O4-modified amphiphilic polyurethane nanoparticles with good stability as magnetic-targeted drug carriers

In order to obtain polyurethane micelles with targeting property and excellent stability, Fe 3 O 4 -modified magnetic amphiphilic polyurethane (MAPU) was successfully synthesized by grafting amphiphilic polyurethane to the surface of Fe 3 O 4 nanoparticles. The structure of MAPU was confirmed by Fourier-transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy ( 1 H NMR), gel permeation chromatography and thermogravimetric analyzer. MAPU could form micelles with the particle size of less than 45 nm, and the micelles showed excellent stability of anti-dilution and storage, determined by dynamic light scattering. MAPU micelles had superparamagnetic property, and magnetically targeted property in HeLa cells measured by vibrating sample magnetometer (VSM) and Prussian blue staining method, respectively. Methyltetrazolium (MTT) assay experiment indicated that MAPU micelles were almost non-cytotoxic. In addition, MAPU micelles could encapsulate hydrophobic model drugs such as Indometacin (IMC) and had a release-sustained effect for IMC.