Volume 112, Issue 4

The present paper describes a simple method for the determination of uranium in uranium process stream solutions by reversed-phase liquid chromatographic method using C18 column, mixture of α-hydroxy isobutyric acid and methanol as eluent and flow-through spectrophotometer detector. This method has an advantage that interfering elements like rare-earth elements do not retain on the column and elute near the solvent peak thereby not interfering with uranium elution peak. Different eluents and parameters like pH, concentration of eluent are studied for the purpose. The spiking standard recovery was found to be more than 90 %. The developed method has been compared with other techniques and found to be in agreement.

The handling and analysis of gaseous tritium is of interest for hydrogen isotope separation experiments. In this work, we present an easy-to-handle setup for catalytic oxidation to HTO, recovering all of the initially dosed gaseous tritium as determined by LSC, using CuO as a catalyst at a reaction temperature of 900 °C. Aiming to reduce cocktail waste, the LSC determination was downscaled to a microfluidic setup. The performance was evaluated based on the counting efficiency, which was shown to decrease significantly, as the sample volume was reduced to µl amounts, while no changes were observed over a wide range of sample-to-cocktail ratios.

Detecting nuclear radiation presents a distinctive challenge, particularly with neutrons, which are neutral particles. The method of direct detection involves the utilization of a converter material, acting as an intermediary. Boron plays a pivotal role in this process, reacting with thermal neutrons to generate alpha particles and lithium, with a notable energy release of 2.314 MeV during the 10 B (n,α) 7 Li reaction. This facilitates effective identification and measurement of neutrons in radiation detection systems. The paths of the particles α (for E  = 1.474 MeV) and Li (for E Li  = 0.842 MeV). The active medium of the nuclear detector, typically a gas, undergoes ionization by these highly charged particles, or they form ion pairs that are subsequently collected by electrodes to produce the signal at the detector’s output. Various deposit methods can be used for this purpose, electrophoresis offers a distinct advantage in terms of both simplicity and precision. This study details the utilization of the electrophoresis technique for the deposition of boron on the tube walls of prototype detectors developed within our laboratory.

In this study, preclinical evaluation and dosimetric estimation of [ 64 Cu]Cu-BPAMD, as a new bone-seeking agent for PET imaging, was studied. [ 64 Cu]Cu-BPAMD was produced with a specific activity of 8.7 GBq/µmol and radiochemical purity (R.P.) of >98 %. The HA binding results showed the binding of nearly all [ 64 Cu]Cu-BPAMD complex to HA at about 15 mg. Biodistribution studies in the male Syrian rats indicated considerable accumulation in the bone with negligible uptake in the other organs. The bone surface and the bone marrow receiving 0.199 and 0.092 mGy/MBq, respectively, are the organs with the most absorbed dose. This study confirms the production of [ 64 Cu]Cu-BPAMD with high R.P. showing high potential for PET-imaging of bone metastases. The lower absorbed dose of mainly human organs compared to 68 Ga-BPAMD can be considered one of the advantages of this new radiolabeled compound.

In this experimental work, guar gum powder was exposed to gamma radiation from a 60 Co source at absorbed doses of 0, 10, 30, 50, 80, 100, 150 kGy at dose rate of 1.62 Gy/s. Raman spectroscopy was applied to measure the intensity of the samples ranging from of 500–4600 cm −1 . The intensity versus Raman shift was evaluated at 3800–4000 cm −1 . Then the curve was fitted linearly. The slope of the lines was determined in each absorbed dose. Results indicated that the absolute values of the slope of each line were enhanced with increasing the absorbed dose. This trend was linear within the absorbed dose ranging from of 0–50 kGy, in which was saturated after 80 kGy. Results showed that guar gum can be applied as a passive dosimeter at radiation processing level.

Antimicrobial resistance (AMR) as one of the world’s most pressing public health problems needs immediate attention, because it has the ability to affect the human healthcare, agriculture, and veterinary industries. Despite warnings about overuse and their implications, antimicrobials are overprescribed worldwide for humans and animals, which leads to the promotion of resistant microorganisms such as bacteria. Food is a medium for exposure to or transfer of residues of the drugs and can contribute to the burden of the pharmaceuticals associated with development of AMR. Studying on residues of veterinary drugs in foods is essential in the fight against AMR. Herein, we introduce a new method for visualizing the residues of a veterinary drug in animal matrices using radionuclides, called “Depletion Imaging”. Amoxicillin was chosen to be the first antimicrobial for this study. The drug was labeled with [ 62 Zn/ 65 Zn] ZnCl 2 . Radiolabelled amoxicillin and non-labeled amoxicillin were administrated to rainbow trout fish simultaneously. To enable visualization of the remaining residues of amoxicillin in fish, In-vivo positron emission tomography (PET) imaging was done at different intervals from 30 min to 21 days after administration. Evaluation of the amount of radiolabelled amoxicillin in fish was done using a high purity germanium (HPGe) nuclear detector, and enzyme linked immunosorbent assay (ELISA) technique was used for the non-labeled drug. In this study, a comprehensive method for in-house production of zinc radioisotopes was also included. The results showed that depletion imaging and biodistribution study based on gamma spectroscopy of radionuclides in tissues, is a precise method for accurate understanding of the drug’s distribution, metabolic and excretory profile.

In this study, alpha spectrometry and neutron activation analysis were applied to assess the mass accumulation rate, contamination history, and ecological risk of the Sundarban mangrove sediments. The mass accumulation rates of sediments using 210 Pb dating determined for the first time in this area ranged from 0.068 to 3.20 kg m −2  y −1 , with an average of 0.61 kg m −2  y −1 . The contamination history of 11 metal(loid)s (Al, Ca, V, Cr, Fe, Ni, Cu, Zn, As, Hg, and Pb) was assessed. Different environmental contamination indices suggested that Sundarban mangrove sediments were contaminated by As. Considering different sediment quality guidelines, it was observed that Cr, Ni, and As posed occasional adverse biological effects on marine organisms. Multivariate statistical approaches were applied to elucidate the origin and transport behavior of the studied metal(loid)s in the mangrove ecosystem which suggested that sources of metal(loid) pollution were both anthropogenic and geogenic. The results from this study should improve the knowledge of metal contamination and ecological risk to biota to develop new strategies and enlarge management practices to save sensitive mangrove ecosystems.