Radiolabeled florescent-magnetic graphene oxide nanosheets: probing the biodistribution of a potential PET-MRI hybrid imaging agent for detection of fibrosarcoma tumor.

PURPOSE: Radiolabeled graphene oxide (GO) nanosheets has been one of the most extensively studied nanoplatform for in vivo radioisotope delivery. Herein, we describe the functionalization of the surface of GO nanosheets with Fe3O4 magnetic nanoparticles, cysteine amino acid as an interface ligand, and cadmium telluride quantum dots. MATERIALS AND METHODS: To enable In vivo PET imaging, the GO@Fe3O4-cys-CdTe QDs were labeled with 68Ga to yield [68Ga] Ga-Go@ Fe3O4-Cys-CdTe QDs. Furthermore, serum stability tests were performed and the biological behavior of the nanocomposite was evaluated in rats bearing fibrosarcoma tumor. RESULTS: Liver, blood and tumor were the most accumulated sites at 1 h after the injection, and the radiolabeled nanocomposite as a PET/MRI imaging agent showed fast depletion from body and acceptable tumor uptake. CONCLUSION: Magnetic (Fe3O4) and fluorescent components (CdTe QDs) along with a positron-emitting radionuclide will help to design a multimodal imaging system (PET/MRI/OI) which will offer the advantages of combined imaging techniques and further possible used in localized radionuclide therapy. Overall, [68Ga] Ga-GO@Fe3O4-cys-CdTe QDs nanocomposite shows great promise as a radiolabeled imaging agent owing to high accumulation in tumor region.

Study of double-using ultrasonic effects on the structure of PbO nanorods fabricated by the sonochemical method.

In this study, lead oxide (PbO) nanostructures are fabricated by an ultrasound-assisted sonochemical method, and re-ultrasonic effects on them are investigated. In the synthesis process, lead nitrate powder is used as a precursor, and potassium hydroxide serves as a precipitation agent. The resulting samples are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and Fourier transform-infrared spectroscopy (FT-IR). Re-ultrasound is also performed to terminate the growth of the PbO nanorods, stabilize them, and preserve their morphology. According to the XRD results, the re-ultrasonic effect did not change the crystal phases, and the tetragonal and orthorhombic crystal phases were preserved. The effect of the calcination time was investigated too; an increase in it led to a decrease in the irregular nanorods size but an increase in the crystallite size.