Novel Magnetic-Luminescent Janus Nanoparticles for Cell Labeling and Tumor Photothermal Therapy

Magnetic-luminescent nanocomposites have multiple uses including multimodal imaging, magnetic targeted drug delivery, and cancer imaging-guided therapies. In this work, dumbbell-like MnFe₂ O₄ -NaYF₄ Janus nanoparticles are synthesized via a two-step thermolysis approach. These synthesized nanoparticles exhibit stability in aqueous solutions and very low cytotoxicity after poly(acryl amide) modification. High cellular uptake efficiency is observed for the folic acid-conjugated MnFe₂ O₄ -NaYF₄ in human esophagus carcinoma cells (Eca-109) due to the upconversion luminescence properties as well as the folate targeting potential. The MnFe₂ O₄ -NaYF₄ also strongly absorbs light in the near-infrared range and rapidly converts to heat energy. It is demonstrated that Eca-109 cells incubated with MnFe₂ O₄ -NaYF₄ are killed with high efficiency after 808 nm laser irradiation. Furthermore, the growth of tumors in mice (grown from Eca-109 cells) is highly inhibited by the photothermal effects of MnFe₂ O₄ -NaYF₄ efficiently. Histological analysis reveals no pathological change and inflammatory response in heart, liver, spleen, lung, or kidney. The low toxicity, excellent luminescence, and highly efficient photothermal therapy properties of MnFe₂ O₄ -NaYF₄ Janus nanoparticles illustrated in this work support their vast potential for nanomedicine and cancer therapy.