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"Isotope harvesting" is a technique that offers access to exotic radionuclides created as by-products during nuclear science research. Ongoing exploratory work at the National Superconducting Cyclotron Laboratory (NSCL) is directed towards the production and extraction of rare radionuclides from a flowing-water target and intends to pave the way for future harvesting efforts at the upcoming Facility for Rare Isotope Beams (FRIB). Here we present the collection of 62Zn from an aqueous matrix irradiated with a 150 MeV per nucleon 78Kr beam, while synergistically capturing other gaseous reaction products. In addition to the production rate for 62Zn (9.08(30) × 10−5 62Zn per incoming 78Kr), the rates of formation for several other radionuclides were determined as well. The purification of 62Zn from a large number of co-produced radionuclides was performed by anion exchange chromatography, allowing the isolation of 80.5(5.2)% of the generated 62Zn. With the decay of 62Zn the radioactive daughter 62Cu is generated, and with the isolation of pure 62Cu eluate, the principle of a medical radionuclide generator could be demonstrated. To illustrate the applicability of the obtained 62Zn, the isolated product was used in free and DTPA-labelled form in a proof of principle plant uptake study with garden cress employing phosphor imaging for visualization. [ABSTRACT FROM AUTHOR]

A durable and ready to use 68Ge-68Ga generator column material is required for its routine use in radiopharmaceutical procedures. The present work comprises preliminary studies for development and evaluation of chitosan-TiO 2 based microsphere (C-TOM) composite towards its competence as a column material. The batch uptake studies showed higher distribution coefficients for 68Ge vis-à-vis 68Ga in the complete concentration range of HCl examined (0.01–1 mol.L−1). Furthermore, C-TOM showed enduring physical and chemical stability in 0.01 mol.L−1 HCl with persistent 68Ga elution profiles (>95%) and negligible 68Ge breakthrough (2 × 10−4%) for the preliminary evaluation period of ∼2 months. Overall, the studies indicated that, 68Ga with high radionuclidic purity (≥99.99%) can be eluted routinely in a small volume (∼1.5 mL) of 0.01 mol.L−1 HCl proving its potentials as a novel solid phase extractant for 68Ge/68Ge generator system. Image 1 • Novel approach towards synthesis of chitosan-TiO 2 microsphere (C-TOM). • Superlative physical and chemical stability of C-TOM in 0.01 M HCl. • Separation of 68Ga from 68Ge with high radionuclidic purity. • Consistent 68Ga elution profile with low 68Ge breakthrough. • Possible application of C-TOM as a potential 68Ge/68Ga generator material. [ABSTRACT FROM AUTHOR]

Accumulation of triphenylphosphonium (TPP) is normally observed in the mitochondria from the extracellular spaces due to the high difference in plasma membrane potential of the mitochondria. In the cancer cells, the mitochondrial membrane potential gap is higher as compared to that of normal cells resulting in elevated uptake of TPP. Silica nanoparticles (SNPs) being widely developed and used for biomedical applications, in this study, we tried to modify the surface of SNPs with varying amounts of TPP to verify their possible application as a positron emission tomography (PET) agent. The studies confirmed that the high level of TPP loading on the surface of SNPs possess higher positive charge (+ 31.5 mV). Owing to this behavior of plasma membrane potential of cancerous cells the uptake of positively charged SNPs was much higher in tumor cells than that of normal cells which was confirmed by PET imaging. [ABSTRACT FROM AUTHOR]

The present work investigates the role of increase in the basicity of organophosphorus extractant (dialkylalkyl phosphonates) on the uptake of actinides and fission products vis-à-vis tributyl phosphate (TBP), currently employed as a universal extractant. Two dialkylalkyl phosphonates viz. dibutylpropyl phosphonate (DBPrP) and dibutylpentyl phosphonate (DBPeP) were synthesized, characterized and evaluated for their solvent extraction behavior towards U(VI), Th(IV), Eu(III) and Tc(VII) in nitric acid medium ranging from 0.01-6 M. It was observed that increasing the basicity of the phosphoryl oxygen enhanced the uptake of the actinides and the distribution coefficient values were significantly larger as compared to TBP. The limiting organic concentration (LOC) value was estimated for Th(IV) for these extractants and compared with the TBP system. The separation factors of actinides with phosphonates over Tc(VII) are distinctly better than that with TBP. [ABSTRACT FROM AUTHOR]

Highlights: [•] Chromatographic separation of 90Y from 90Sr. [•] Sequential use of Sr-selective column and Y-selective column. [•] Perchloric acid is better medium than hydrochloric acid/nitric acid. [•] Final product in 0.01M EDTA is amenable for radiopharmaceutical application. [ABSTRACT FROM AUTHOR]

In biological applications of nanoparticles, the control of physicochemical properties such as size, shape, and surface charge enables the improvement of their ability for cancer target. In addition, it can be tracked by labeling in these nanoparticles with medical radionuclides for detection of cancer. Here, we report novel chelator-free direct-labeling of hierarchical hematite nanoclusters with 89Zr (89Zr-IONCs) through hydrothermal reaction to develop biocompatible radiolabeled nanoparticle which is effective for tracking cancer cells. Characterization of 89Zr-IONCs revealed that the zirconium ions were tightly bound inside hematite crystals with intervals of glutamic acid absorbed on their surfaces having spindle shape with a mean width of 180 nm and length of 80 nm. This method showed promising radiolabeling yield and labeling stability in biological environments which was ≥ 99%. Their high colloidal stability in serum was considerably maintained for the span of a week by the formation of protein corona with the hematite nanoclusters. For the result of biological evaluations, cytotoxicity assay provides evidence of the high biocompatibility of the product. The elevated in vitro cellular uptake of 89Zr-IONCs for the CT-26 and A549 cells was observed. Furthermore, we found that the spindle shape of 89Zr-IONCs was more effective for cell internalization compared with round shape due to the extended interfacial surface area with a cell membrane when their endocytosis is started. Our one-pot synthesized 89Zr-incorporated hematite nanoclusters show the promising approach for a simple and highly stable chelator-free radiolabeling system, which exploits the non-toxic potential carrier to target cancer cells. [ABSTRACT FROM AUTHOR]