METHODS: Oleylamin-coated IONs (ION-Ol) were synthesized and surface of the IONs was modified using protoporphyrin (PP) and trastuzumab (TZ) to develop the TZ-conjugated SPION-porphyrin [ION-PP-TZ]. The structure, morphology, size, and cytotoxicity of all samples were investigated using Fourier-transform infrared spectroscopy (FT-IR), Transmission electron microscopy (TEM), X-ray powder diffraction (XRD), WST-1 assay, respectively. In addition to MRI and in vitro laser irradiation (808 nm, 200 mW) to determine the r2 values and photothermal ablation.
RESULTS: The sizes of monodispersed nanoparticles were measured in rang 5.74-7.17 nm. No cytotoxicity was observed after incubating MCF 7 cells under various Fe concentrations of nanoparticles and theranostic agents. The transverse relaxation time of the protoporphyrin conjugated to IONs (52.32 mM-1s-1) exceeded that of ION-Ol and TZ-conjugated ION-PP. In addition, the in vitro photothermal ablation of ION-PP-TZ revealed a 74 % MCF 7 cell reduction after 10 min of at the highest Fe concentration (1.00 mg Fe/mL).
CONCLUSIONS: In summary, the water-soluble ION-PP-TZ is a promising bimodal agent for the diagnosis and treatment of human epidermal growth factor receptor 2-positive breast cancer cells using a T2 MRI contrast agent and photothermal therapy.