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.

In vivo toxicity assessment of non-cadmium quantum dots in BALB/c mice.

Along with widespread usage of QDs in electronic and biomedical industries, the likelihood of QDs exposure to the environment and humans is deemed to occur when the QD products are degraded or handled as waste for processing. To date, there are very few toxicological reports available in the literature for non-cadmium QDs in animal models. In this work, we studied the long term in vivo toxicity of InP/ZnS QDs in BALB/c mice. The biodistribution, body weight, hematology, blood biochemistry, and organ histology were determined at a very high dosage (25 mg/kg) of InP/ZnS QDs over 84 days period. Our results manifested that the QDs formulation did not result in observable toxicity in vivo within the evaluation period, thereby suggesting that the InP/ZnS QDs can be utilized as optical probes or nanocarrier for selected in vivo biological applications when an optimized dosage is employed. FROM THE CLINICAL EDITOR: This study investigated the toxicity of quantum dots in BALB/c mice, and concluded that no organotoxicity was detectable despite of using high concentration of InP/ZnS quantum dots with prolonged exposure of 3 months.