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The rapid synthesis of two radiofluoronicotinamide derivatives, namely, [18F]MEL050 and [18F]MEL-2F has been simply performed starting from commercial materials. [18F]MEL-2F is a new, potential analogue PET-probe for melanoma imaging. [18F]MEL050 is already an excellent PET imaging probe for early specific diagnosis. The synthesis involves coupling step to obtain the precursor followed by radiofluorination. During the synthesis of the precursors different coupling reagents, such as HBTU, TFFH, HOBT, COMU and PyCIU have been applied. PyClU was found the best to reduce the coupling period to

Iodobenzamides are reported to possess some affinity for melanoma. This study describes the synthesis of a new benzamide analogue, N-(2-diethylamino-ethyl)-4-(4-chloro-nicotinamido)-5-[125I]iodo-2-methoxybenzamide ([125I]H4) designed to target melanoma. The synthesis was simply achieved in four steps. There were two PyCIU/DIPEA amide condensations and a transfer hydrogenation using an ammonium formate hydrogen donor. The radioiodination step was carried out with 125I via an electrophilic substitution reaction. The reaction conditions were optimized. The labeled compound was purified by HPLC. The maximum radiochemical yield was found to be 78% at a radiochemical purity of 98%. All compounds were characterized by MS and NMR techniques. The log P value for [125I]H4 was found as 3.96±0.5.

Magnetoelectric biferroic nanocomposite with composition 0.5Ni0.5Zn0.5Fe2O4 + 0.5BaTiO3 was synthesized by ceramic technique. The structural and electrical characterizations of the investigated nanocomposite are discussed and reported. The formation of nanosized composite with two separate phases was confirmed by X-ray diffraction, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The variation of dielectric constant (e'), dielectric loss factor (e”) and the ac conductivity (σac) of 0.5Ni0.5Zn0.5Fe2O4 + 0.5BaTiO3 was investigated as a function of both frequency and temperature. Thermal hysteresis (first-order transition) was obtained during heating (300 - 830 K) and cooling runs (830 - 300 K). The exact transition temperature and the amount area of the thermal hysteresis depend on applied ac electric field. The delay (lagging) time between heating and cooling processes was estimated from the hysteresis loop area versus frequency. The conduction mechanism in the investigated samples was explained according to different models. This study enhances the use of this prepared system in memory applications.

This study describes a fast and efficient method for radiolabeling of etodolac with iodine-125 [125I], where both chloramine-T and iodogen were used as oxidizing agents. The labeling reaction was carried out via electrophilic substitution of hydrogen atom with the iodonium cation I+. The labeling yield was found to be influenced by different factors such as drug concentration, pH of the reaction mixtures, different oxidizing agents, reaction time, temperature and different organic media. The radiochemical yield (RCY) was determined by TLC system using methylene chloride:ethyl acetate (3:7 v/v) as a developing solvent and by electrophoresis using cellulose acetate moistened with 0.02 M phosphate buffer pH 7. The maximum radiochemical yield of [125I]Etodolac (87.7%) was obtained. Labeled etodolac shows a good localization in inflamed muscle. It excretes mainly via kidney and to some via liver.

This work assesses the potential of an adsorptive material, Dowex 50w-x8, for the separation of indium ions from cadmium ions in aqueous media. The adsorption behavior of Dowex 50 w-x8 for indium and cadmium ions was investigated. The effect of pH, initial concentration of metal ions, the weight of resins, and contact time on the sorption of each of the metal ions were determined. It was found that the adsorption percentage of the indium ions was more than 99% at pH 4.0. The result shows that In (III) was most strongly extracted, while Cd(II) was slightly extracted at this pH value. The recovery of In(III) and Cd(II) ions is around 98% using hydrochloric acid as the best eluent.

The present study is performed to compare the electrophilic substitution radioiodination reaction of two non-steroidal anti-inflammatory drugs namely, Piroxicam (Pirox) and Meloxicam (Melox) with 125I where both chloramine-T (CAT) and iodogen were used as oxidizing agents. The factors affecting the percent of radiochemical yields such as drug concentration, pH of the reaction mixtures, different oxidizing agents, reaction time, temperature and different organic media were studied to optimize the conditions for labeling of Pirox and Melox and to obtain high radiochemical yields. The maximum radiochemical yield of 125I-Piroxicam (125I-Pirox) was 94% using 3.7 MBq of Na125I, 0.4 mM of Pirox as substrate, 3.6 mM of chloramine-T (CAT) as oxidizing agent in acetone at neutral pH = 7 and at 60 °C within 20 min where the maximum radiochemical yield of 125I-Melox was 92% using 0.7 mM of Melox as substrate, 0.62 mM of iodogen as oxidizing agent in acetone at neutral pH = 7 and at 25 °C within 30 min. The radiochemical yields were determined by TLC and high-pressure liquid chromatography (HPLC). Tracers showed good localization in inflamed muscle either septic or sterile. The collected data indicates that Pirox and Melox can be used as antiinflammatory imaging agents at 24 and 2 h post injection, respectively.

A procedure for radioiodination of colchicine with iodine-125 is carried out via an electrophilic substitution reaction. The reaction parameters studied were colchicine concentration, pH of the reaction mixture, reaction time, temperature, different oxidizing agents and different organic media to optimize the conditions for the labeling of colchicine and to obtain a high radiochemical yield of the 125I-colchicine (125I-Col). Using 3.7 MBq of Na125I, 1.25 mM of colchicine as substrate, 1.1 mM of chloramine-T (CAT) as oxidizing agent in ethanol at 60°C for 5 min, a maximum radiochemical yield of 125I-Col (60%) was obtained. The specific activity of 125I-Col obtained was 44.4 MBq/0.5 mmol, and the labeled compound was not completely separated and purified from Col by means of high-pressure liquid chromatography (HPLC), so the uncertainty in the purity may affect the distribution and clearance routes due to the expected competition between 125I-Col and Col. The biological distribution in normal mice indicates the suitability of radioiodinated colchicine for imaging of muscles. Copyright © 2008 John Wiley & Sons, Ltd.

The effect of post- and pre-high doses of γ–radiation in CR-39 plastic detectors has been studied in the dose range of 3×101−106 Gy. Some properties like bulk-etch rate (V B), track-etch rate (V T), sensitivity (V T/V B) and efficiency have been found out for different gamma doses from a 60Co source in CR-39. It is found that V B and V T remain almost invariant up to gamma doses of 104 Gy. Then they start increasing slowly till 105 Gy. Between 105 Gy and 106 Gy there is a sharp increase of V B and V T values for pre- and post-gamma exposed samples. The present data are compared with the previous literature.

Thorium-to-uranium ratios have been determined in different soil samples using CR-39 and LR-115-II solid-state nuclear track detectors (SSNTDs). A calibration method based on determination of SSNTD registration sensitivity ratio for α-particles of thorium and uranium series has been developed. Thorium and uranium contents of the standard soil samples have been determined and compared with its known values. There is a good agreement between the results of this method and the values of standard samples. The method is simple, inexpensive, non-destructive and has a wide range of applications in environment, building materials and petroleum fields.

An alpha track was selected through a number of successive CR-39 sheets in a high energy nuclear reaction experiment. The experiment was aimed at identifying particles emitted at an angle of 25° to the beam direction when bombarding a copper disk with relativistic fluorine ions. Most of these particles were identified as protons and alpha particles. The experiment showed that the inlet energy of an alpha particle to be detectable in CR-39 plastic is 53.4 MeV per nucleon. The CR-39 range of such particles is ∼2 cm long. The corresponding range for a proton is ∼1 mm long. The track diameter at positions on the track length can display the damage as a function of the depth in the CR-39 material. In addition, the track length is measured along the particle trajectories in CR-39 sheets for a single track as a function of residual range in the CR-39 material. The restricted energy loss (REL) for alpha tracks in CR-39 is calculated using the Henke–Benton computer program. Comparison between the REL and the damag...

The formation of etched tracks in solid-state nuclear track detectors is usually described by assuming an unequivocal correlation of the etch-rate ratio with the energy loss of charged particles. For alpha particles, this assumption could be verified within the scatter of the experimental data. In this article, the dependence of the depth (x) on the track etch rate (V T) was determined experimentally by track length measurement. It is found that the track etch rate as a function of the depth within the detector follows the Bragg curve. The track etch rate has been found to be described by a generalization of the restricted energy loss, in good approximation along the trajectories of alpha particles.