Facile Fabrication of Fe3O4@poly(acrylic) Acid Based Ferrofluid with Magnetic Resonance Imaging Contrast Effect

Magnetic resonance imaging (MRI) has emerged as one of the most promising techniques, which employs nanoscience and imaging technology, for early diagnosis of the cancers. In this work, magnetic nanoparticles of Fe3O4@ poly(acrylic) acid (PAA) were synthesized using a low cost thermal decomposition method from iron ions precursor and utilized as a signal agent for MRI imaging. The Fe3O4 magnetic nanoparticles obtained from FeCl2.4H2O precursor at the reaction temperature of 315 °C in 1‐octadcene solvent are of spherical shape with average diameter of 8.4 nm and high saturation magnetization (Ms) of 60.05 emu/g. After phase transferred with PAA, the magnetic Fe3O4@PAA fluid is highly stable in a wide range of pHs solution (5 ‐ 9) and wide range of NaCl concentrations (50 ‐ 300 mM) with zeta potential of −35.7 mV. The prepared Fe3O4@PAA fluid showed noncytotoxicity to the Hep‐G2, MCF‐7, RD cancer cell line and Vero healthy cell line. MRI in‐vitro results showed that transverse relaxation rate r2 was around 158.4 mM−1s−1 and the signal intensity was not affected by the pHs solution and NaCl concentrations. In‐vivo test on rabbit revealed the clear observation of rabbit's body parts after injection of the Fe3O4@PAA magnetic fluid with retention time of 90 minutes in the body. This paper reports the fabrication of Fe3O4@ poly(acrylic) acid (PAA) magnetic nanoparticles using a low cost thermal decomposition method. The resultant Fe3O4@PAA fluid was not toxic to theHep‐G2, MCF‐7, RD cancer cell lines and Vero healthy cells. MRI in‐vitro showed that transverse relaxation rate r2 was around 158.4 mM−1s−1 and was not affected by the pH and NaCl concentrations. In‐vivo test on rabbit showed that the imaging of body parts was clearly observed after the injection of the Fe3O4@PAA magnetic fluid.