Microwave assisted synthesis of FeO stabilized ZrO nanoparticles - Free radical scavenging, radiolabeling and biodistribution in rabbits.

AIMS

In vivo biodistribution of radio labeled ZrO nanoparticles is addressed for better imaging, therapy and diagnosis. Nanoparticles are synthesized by microwave assisted sol-gel technique using FeO as a stabilizer. Antioxidant assay, hemolytic activity in human blood and biodistribution in rabbits was explored to study the therapeutical as well as in vivo targeted diagnostic applications of as synthesized nanoparticles.

MAIN METHODS

FeO stabilized zirconia nanoparticles are synthesized using microwave assisted sol-gel method. Microwave (MW) powers are varied in the range of 100 to 1000 W. As synthesized nanoparticles are evaluated using different characterizations such as X-ray diffractometer, scanning electron microscope, Raman spectroscopy, impedance analyzer, Vickers micro hardness indenter, FTIR, and UV-Vis spectroscopy. In vitro activity of synthesized nanoparticles is checked in freshly extracted human blood serum. To study biodistribution of FeO stabilized zirconia nanoparticles in rabbit, technetium-99 m was used for labeling purpose. The labeling efficacy and stability of labeled nanoparticles are also measured with instant thin layer chromatography (ITLC) method. Intravenous injection of Tc-FeO stabilized zirconia nanoparticles (0.2 ml), containing 110 MBq of radioactivity, is performed to study the biodistribution; nanoparticles are injected into the ear vein of animal (rabbit).

KEY FINDINGS

Zirconia (ZrO) nanoparticles (NPs) are stabilized using FeO that were prepared by means of microwave assisted sol-gel method. Crystallite size (20 nm) agrees well with the values required to stabilize tetragonal zirconia (t-ZrO). Volume shrinkage results in high value of hardness (1369). Dielectric constant values, compatible for biomedical application, are observed for tetragonally stabilized samples. Low value of hemolytic response is observed for FeO stabilized ZrO NPs. Tc radio labeled ZrO NPs proved to be potential candidate to study biodistribution. Biodistribution studies show stability of radiolabeled NPs in the original suspension as well as in blood serum. CT scan of rabbit is performed for several times to check the biodistribution of NPs with time and survival of rabbit. Results suggest that these NPs can also be used as targeted nanoparticles as well as variants of drug payload carrier.

SIGNIFICANCE

Results signify that FeO stabilized ZrO nanoparticles synthesized by microwave assisted sol-gel method may be considered as "all-rounder" nanoplatform and are safe enough to be used in diagnostic as well as therapeutic purposes.