Photodynamic therapy evaluation of methoxypolyethyleneglycol-thiol-SPIONs-gold-meso-tetrakis(4-hydroxyphenyl)porphyrin conjugate against breast cancer cells.

Magnetic field enhanced photodynamic therapy is an effective non-invasive technique for the eradication of cancer diseases. In this report, magnetic field enhancement of the photodynamic therapy (PDT) efficacy of a novel methoxypolyethyleneglycol-thiol-SPIONs-gold-meso-tetrakis(4-hydroxyphenyl)porphyrin conjugate (nano-drug) against MCF-7 breast cancer cells was evaluated. The nano-drug exhibited excellent blue and red emissions under suitable ultraviolet (380 nm) and visible (430 nm) excitations and was well taken up by the cells without any significant dark cytotoxicity after 24 h post-incubation. However, after exposure of cells to light for about 15 min, high rate of cell death was observed in a dose-dependent manner. In addition, the cells that were exposed to external magnetic field displayed higher phototoxicity than the non-exposed cells. Altogether, these results suggest that the nano-porphyrin drug system can function as a new promising magnetic-field targeting agent for theranostic photodynamic eradication of cancer diseases.