Monodispersed Fe3O4 magnetic nanoparticles (MNPs) having size of 7 nm have been prepared from iron oleate and made water dispersible by functionalization for biomedical applications. Three different reactions employing thioglycolic acid, aspartic acid and aminophosphonate were performed on oleic acid coated Fe3O4. In order to achieve a control on particle size, the pristine nanoparticles were heated in presence of ferric oleate which led to increase in size from 7 to 11 nm. Reaction parameters such as rate of heating, reaction temperature and duration of heating have been studied. Shape of particles was found to change from spherical to cuboid. The cuboid shape in turn enhances magneto-crystalline anisotropy (Ku). Heating efficacy of these nanoparticles for hyperthermia was also evaluated for different shapes and sizes. We demonstrate heat generation from these MNPs for hyperthermia application under alternating current (AC) magnetic field and optimized heating efficiency by controlling morphology of particles. We have also studied intra-cellular uptake and localization of nanoparticles and cytotoxicity under AC magnetic field in human breast carcinoma cell line.

This investigation reports the preparation of agglomerated Fe 3 O 4 nanoparticles and evaluation of its utility as a viable carrier in the preparation of radiolanthanides as potential therapeutic agents for the treatment of arthritis. The material was synthesized by a chemical route and characterized by XRD, FT-IR, SEM, EDX and TEM analysis. The surface of agglomerated particle possessed ion pairs (-O À :Na + ) after dispersing particles in a NaHCO 3 solution at pH = 7 which is conducive for radiolanthanide (*Ln = 90 Y, 153 Sm, 166 Ho, 169 Er, 177 Lu) loading by replacement of Na + ions with tripositive radiolanthanide ions. Radiolanthanide-loaded particulates exhibited excellent in vitro stability up to B3 half-lives of the respective lanthanide radionuclides when stored in normal saline at 37 1C. The radiochemical purities of the loaded particulates were found to be retained to the extent of 470% after 48 h of storage when challenged by a strong chelator DTPA present at a concentration as high as 5 mM, indicating fairly strong chemical association of lanthanides with agglomerated Fe 3 O 4 nanoparticles. Biodistribution studies of 90 Y and 166 Ho-loaded particulates carried out after intra-articular injection into one of the knee joints of a normal Wistar rat revealed near-complete retention of the radioactive preparations (498% of the administered radioactivity) within the joint cavity even after 72 h post injection. This was further confirmed by sequential whole-body radio-luminescence imaging. These experimental results are indicative of the potential use of radiolanthanide-loaded agglomerated Fe 3 O 4 nanoparticles for the treatment of arthritis.

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Synthesis of intrinsically radiolabeled nanoparticles is an emerging concept in cancer theranostics and is expected to play an imperative role in translating nanotechnology research into the nuclear medicine industry. In order to reduce reliance on cyclotron produced 64 Cu (t 1/2 = 12.7 h, EC 45%, β + 17.9%, β − 37.1%) and increase global accessibility of this radioisotope for preclinical and clinical investigations, we have explored the feasibility of using neutron-activated 64 Cu produced in research reactors for potential use in cancer theranostics. A viable strategy has been developed for production of 64 Cu in medium-flux research reactors and its utilization toward industrial-scale (GBq level) synthesis of intrinsically radiolabeled 64 CuS nanoparticles (∼30 nm particle size). The synthesis procedure was easily executable in a hot cell equipped with remotely operable gadgets and 64 CuS nanoparticles could be synthesized in a form suitable for clinical administration. The stability of the nanoparticles under physiological conditions was established by detailed in vitro studies in phosphate buffered saline (PBS) and mouse serum media. The biological efficacy of intrinsically radiolabeled 64 CuS nanoparticles was studied in C57BL/6 mice bearing melanoma tumors. The results of the biodistribution studies revealed significant tumor uptake (4.64% ± 1.71%ID/g) within 4 h post-injection (where %ID is the percent injected radioactivity dose), with good tumor-to-background contrast. Collectively, the promising results obtained in this study suggest that the concept of intrinsically radiolabeled nanoplatforms can be employed to facilitate widespread utilization of neutron-activated 64 Cu in nuclear medicine industry.

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YPO4:Eu 3+ nanoparticles have been prepared in different solvents such as polyethylene glycol (PEG), PEG-diacid and water. These nanoparticles crystallize in mixture of tetragonal and hexagonal phases. Ratio of tetragonal to hexagonal phases in PEG and PEG-diacid mediums is much lower than that in water. Interestingly, luminescence intensity upon excitation at 260 and 395 nm for the sample prepared in water is higher than that for sample prepared in PEG or PEG-diacid. This is because of association of water molecules trapped inside the pores of hexagonal phase and this induces non-radiative rate. In order to study effect of Bi 3+ co-doping on luminescence intensity, we have carried out detail crystal structure evolutions in different solvents. However, luminescence intensity decreases significantly upon Bi 3+ co-doping because it enhances conversion of a mixture into hexagonal phase. Upon heating at 900 o C, luminescence intensity increases significantly because of conversion of hexagonal to tetragonal phase. Increase in lifetime value of Eu 3+ as well as the red light enhancement has been observed in 900 o C heated samples by Bi co-doping.

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