Iodine determination in milk by isotope dilution analysis

Iodine is an essential trace element in the human diet. It is utilized in the synthesis of L-monoiodothyrosine, which is a precursor of the thyroid hormones, thyroxin and triiodothyronin. In this study, a method that can determine iodine concentrations in milk has been developed. The method is based on substoichiometric isotope dilution analysis (IDA). Iodine concentrations were measured in milk, which has been collected from three big cities and environment municipalities of Aegean Region. The iodine concentration ranges were within 436.8 and 896.7 μg/kg in milk samples. Mean iodine concentration was not greatly changed from season to season, between 1998 and 2002. This revised version was published online in August 2006 with corrections to the Cover Date.     

Labeling of ornidazole with iodine-131

Ornidazole (1-(3-chloro-2-hydroxypropyl)-2-methyl-5-nitroimidazole) was labeled with iodine-131 by using iodogen method. Quality controls were performed by instant thin layer chromatography (ITLC) and electrophoresis methods. Labeling yield was 91%. Iodination was carried out by substitution of chloride by iodine-131. Structure was confirmed by¹H-NMR.     

Iodine measurements by isotope dilution analysis in drinking water in Western Turkey

This study was designed to evaluate iodine concentrations in drinking water samples using isotope dilution analysis (IDA) in the Aegean region of Turkey A total of 76 drinking water samples from rural and urban areas in regional cities were analyzed. The mean iodine concentration was 78±27 μg/l and iodine concentration ranges were within 69±26 μg/l and 103±6 μg/l.     

Labeling of apigenin with 131I and bioactivity of 131I-apigenin in male and female rats

Apigenin (4′,5,7-trihydroxyflavone), one of the most common flavonoids, has been shown to possess a variety of biological activities including tumor growth inhibition and chemopreventation. In the present study, apigenin was labeled with ¹³¹I using iodogen method and investigated of its bioactivity. Radiolabeling yield is 98±0.2%, as determined by radio thin layer chromatography (RTLC), electrophoresis and radio high performance liquid chromatography (RHPLC). Besides, structure analysis of synthesized cold iodoapigenin complex were assessed with LCMS/MS and ¹H-NMR. Results of in vitro study indicated a high stability (3 hours) in human serum. Biodistrubition studies are performed in male and female albino Wistar rats. Biodistribution data related to the male rats showed significant uptake in the small intestine. The female rats biodistribution results indicated that the uptake of ¹³¹I-apigenin was high in the intestine and uterus.     

Radiolabeling of codeine with 131I and its biodistribution in rats

Codeine which was extracted from dry capsules of the opium poppy (Papaver somniferum) was purified by HPLC (High Performance Liquid Chromatography) and characterized by NMR (Nuclear Magnetic Resonance) and IR (Infrared) spectroscopy techniques. The purified compound was labeled with ¹³¹I and biodistribution studies were performed in rats. Radioiodinated codeine distributed uniformly in the cerebellum, m.pons, striatum and hypothalamus while the other branch of brain and Stomach, urinary bladder, and small intestine uptakes were significantly higher than other tissues.     

Stability of iodine content in iodized salt

lodization of consumed salts is mandatory in many countries fighting against to iodine deficiency. In salts iodine stability is affected by storage conditions. In this study, stabilization of iodine in salt has been determined by using Isotope Dilution Analysis. Heating, heating with oxidizing agent, incubation by time were the parameters which have been determined. Iodine loss was 41.16% by heating at 200 degrees C up to 24 hours. When the iodized salt heated with oxidized agent iodine loss rose up to 58.46% in 24 hours. Iodine loss mechanism seems similar in both cases. However iodine loss is greater in the presence of H202. After the salt was stored at room temperature with a relative humidity of 30%-45% and in sealed paper bags for three years, 58.5% of iodine content lost in approximately 3.5 years.     

Preparation of L-asparagine complex of technetium-99m

Attempts have been made to employ magnesium oxide as the preconcentration agent for determination of trace metal sin seawater by neutron activation analysis. Hydrous magnesium oxide can efficienthy adsorb most cationic transition metals and rare earths in a simple water system. The adsorption behavior is believed to depend mainly from the association of the cationic species of the metals with MgO ₂ ^2– adsorbent. In seawater matrix some of the metal ions such as Hg²⁺, Ni²⁺, etc. may become inefficiently adsorbed owing to the formation of highly stable metal-chloro complexes with chloride ion. Usually the adsorption efficiencies of the metals can be recovered to be as high as the case in the simple water system if an acidified seawater (to pH1) is subjected to the adsorption experiment. In practice, a large volume of seawater (5 1) is stirred with a small amount of hydrous MgO (1 g). Thereafter, the trace metals adsorbed MgO is separated and taken to be neutron activated. The abundant sodium ion and ubiquitous bromide ion can be obviated by the adsorption process, thereby beneficial to the -spectrometry of the metals enriched on MgO.     

Labeling of Sertraline with 131I and investigation of its radiopharmaceutical potential

Sertraline is an antidepressant drug. Sertraline was labeled with ¹³¹I by using iodogen method. Labeling yield was 85–90% and specific activity was approximately 64.75 GBq/mmol. The purification of radioiodinated Sertraline was performed by Sep Pak C-18 plus and the radiochemical purity was determined to be over 99%. Biodistribution studies were carried out by male Albino Wistar rats. The percentage of injected radioactivity per gram of tissue was calculated, and these data versus time curves were generated for organs and brain regions. The results showed that ¹³¹I labeled Sertraline may be a promising radiopharmaceutical for the investigation of serotonin 5-HT receptor functions of brain.     

In vitro evaluation of radiolabeled (125I) methanol extracts of yarrow in cell lines of MCF-7, PC-3, A-549 and Caco-2

Nowadays, cancer is still the second leading cause of death all over the world. Therefore, natural products which have anticancer and antitumor properties are come into prominence. Achillea family is known with anticancer and antitumor activity. Yarrow which has over a hundred bioactive compounds is a member of Achillea family. In current study; components of yarrow which was obtained after methanol extraction and purification were radiolabeled with ¹²⁵I and effects of these radiolabeled components on the cells were examined with using Caco-2, MCF-7, A-549, PC-3 cell lines. As a result of these studies, seven peaks were obtained and the highest radiolabeling yield was calculated for ¹²⁵I radiolabeled Peak 7 (95.00 ± 7.07, n = 4). To screen the biological properties of these radiolabeled peaks at determined cell lines, our ongoing effort was to evaluate incorporation percentage with time dependent. Furthermore, ¹²⁵I-Peak 7 had highest incorporation ratio for whole cell lines and its incorporation percentage was increased with time dependent. Results of these in vitro studies were compatible with previous in vivo studies and traditional use of yarrow plants.     

Synthesis,radiolabeling and biodistribution of morphine glucuronide (mor-glu)

The aim of this study was to synthesize a glucuronide conjugated morphine derivative which could be labeled with ¹³¹I, as a radiopharmaceutical, and to investigate its radiopharmaceutical potential using biodistribution studies in male Albino Wistar rats. Morphine was extracted from dry capsules of the opium poppy (Papaver somniferum L.). It was conjugated with UDP-glucuronic acid by using UDP-glucuronyl transferase (UDPGT) enzyme rich microsomes, purified by high performance liquid chromatography (HPLC) and characterized by nuclear magnetic resonance (NMR), infrared (IR) spectroscopy and liquid chromatography mass spectroscopy (LC-MS/MS). Normal and receptor blockage biodistribution studies were performed in male Albino Wistar rats. The results of the tissue distribution studies showed that ¹³¹I labeled morphine glucuronide (¹³¹I-mor-glu) uptake in the small intestine, large intestine and urinary bladder was higher than in the other tissues of the rats in the blocked receptor and unblocked receptor. A greater uptake of the radio labeled substance was observed in the hypothalamus and mid brain than in the other branches of the rats’ brains.