Synthesis and characterization of photo-functional magnetic nanoparticles (Fe3O4@HP) for applications in photodynamic cancer therapy

Nowadays, photodynamic therapy (PDT) is a quite promising approach for killing various cancer cells. In this work, we report on photo-functional magnetic nanoparticles conjugated with hematoporphyrin (HP) (Fe3O4@HP) via a simple surface modification process. The microstructure and the magnetic properties of the Fe3O4 nanoparticles were investigated by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and vibrating sample magnetometry (VSM), and the biocompatibility and the photo-killing activity were evaluated using mammalian cells in vitro to confirm the potential of these particles for use as an agent for PDT application. We have demonstrated that the Fe3O4@HP nanoparticles show good biocompatibilities in fibroblast (L-929) and prostate cancer (PC-3) cells and have remarkable photodynamic anticancer activities. Especially, the photo-killing activities for 25, 50, and 100 mu g/ml of Fe3O4@HP were found to be above 86% (86.6, 99.2, and 99.4%, respectively) in PC-3 cells, demonstrating significantly high anticancer effects on prostate cancer cells, these effects depend on the concentration of the Fe3O4@HP nanoparticles. These results indicate that our Fe3O4@HP nanoparticles can be useful for PDT, although further studies to evaluate the cell-death mechanisms in vitro and in vivo will be needed to verify the potential for clinical PDT applications.