Lanthanide-Doped SPIONs Bioconjugation with Trastuzumab for Potential Multimodal Anticancer Activity and Magnetic Hyperthermia.

Iron oxide-based nanoparticles have been modified in their core with holmium(III) in an amount affecting only slightly their magnetic properties. Nanoparticles were conjugated covalently with biomolecule of trastuzumab (Herceptin®), the monoclonal antibody that recognizes cancer cells overexpressing HER2 receptors targeting such nanoparticles to the specified tumor tissues. Systematic studies of Ho3+-doped bioconjugates were carried out as a preliminary step for future replacement of 'cold' Ho with 166Ho radionuclide, emitting 'soft' beta(-) radiation for possible targeted radionuclide therapy. Physicochemical properties of the obtained bioconjugates were subsequently tested for use in magnetic hyperthermia, considered as an effective, low-invasiveness anticancer therapy. With such a system we expect to achieve both: active targeting and multimodal action by simultaneous internal and localized irradiation and magnetic hyperthermia of specific cancers.