Labeling bombesin-like peptide with Tc-99m via hydrazinonicotinamide: description of optimized radiolabeling conditions

WOS: 000276910200008Bombesin (BNN)-like peptides have very high binding affinity for the gastrin-releasing peptide (GRP) receptor. The goal of the current study was to optimize the labeling conditions of a new Tc-99m-radiolabeled BNN-like peptide based on the bifunctional chelating ligand HYNIC using different co-ligands (EDDA and tricine). The radiolabeling conditions (pH, amount of co-ligand, amount of stannous chloride, temperature and reaction time) for newly-formed Tc-99m-tricine-HYNIC-Q-Litorin and Tc-99m-EDDA-HYNIC-Q-Litorin were optimized and evaluated by RHPLC and RTLC. Radiochemical yields for Tc-99m-tricine-HYNIC-Q-Litorin and Tc-99m-EDDA-HYNIC-Q-Litorin were 98.0 +/- A 1.7 and 97.5 +/- A 2.5%, respectively. When EDDA was used as co-ligand, the labeling of Tc-99m-EDDA-HYNIC-Q-Litorin was optimal in the following reaction mixture: HYNIC-peptide: EDDA: 10 mu g/5 mg, pH 3, SnCl2 concentration: 12 mu g/0.1 mL, reaction temperature: 100 A degrees C, reaction time: 15 min. Besides, the optimum conditions were HYNIC-peptide:tricine: 10 mu g/50 mg, pH 5, SnCl2 concentration: 12 mu g/0.1 mL, reaction temperature: 100 A degrees C, reaction time: 15 min for preparing Tc-99m-tricine-HYNIC-Q-Litorin. The manufactured Tc-99m-HYNIC-Q-Litorin conjugates may offer new possibilities for imaging cancer cells expressing bombesin receptors.Scientific and Technological Research Council of TurkeyTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [108S200]The authors gratefully acknowledge the financial support received from the Scientific and Technological Research Council of Turkey, Scientific Project (TUBITAK Number 108S200)

Gamma radiation shielding efficiency of a new lead-free composite material

The aim of the study is to produce a new metal-polymer composite in the form of disc and investigate shielding efficiencies against gamma radiation (137Cs and 131I and 241Am). The composite discs were produced from mixing polymer and different percentage tungsten carbide (50, 60, and 70 %). Compared with lead in same conditions the new material is more lightweight and flexible. Moreover the material’s shielding efficiency is higher than lead also. © 2015, Akadémiai Kiadó, Budapest, Hungary

Preparation, quality control and stability of Tc-99m-cefuroxime axetil

7th International Symposium on Technetium in Chemistry and Nuclear Medicine -- SEP, 2006 -- Bressanone, ITALYWOS: 000251867200020Cefuroxime axetil, a cephalosporin antibiotic used to treat bacterial infections, was investigated to label with Tc-99m. Radiolabeling of cefuroxime axetil was carried out by using stannous chloride method. Effects of pH and stannous chloride amount on the radiolabeling yield were investigated. The radiochemical purity of Tc-99m-cefuroxime axetil was determined by thin layer radio chromatography (TLRC), electrophoresis and high performance liquid chromatography. The maximum radiolabeling yield was 98 +/- 1%

Synthesis of a 99mTc labeled estrogen-derivative and the determination of its radiopharmaceutical potential on rats

An estrogen derivative 1-(3, 17-?-estradiolyl propin-1-yl-3-(1,4,8, 11-tetraazacyclotetradecyl)-propanate (ESTACPA) was synthesized. The product was purified by HPLC and characterized by NMR and IR spectroscopy. The synthesized compound was labeled with 99mTc. The biodistribution studies were performed on female Albino Wistar rats. The rats were sacrificed and their organs were removed. The radioactivities of the organs were counted using a gamma-counter. The activity per gram tissue was calculated and time versus activity curves were generated. The 99mTc-ESTACPA uptake by the uterus and ovary such as ER-rich tissues, were observed. The pancreas and stomach also showed a significant uptake.International Atomic Energy AgencyThe authors thanks for the financial supports from Ege University Research Funds, Afyon Kocatepe University Research Fund and International Atomic Energy Agency (IAEA) and The Scientific and Technical Research Council of Turkey. They are grateful to Schering Alman Ilac Ecza Ticaret Ltd. for supplying the ethynyl estradiol as a gift for chemical synthesis and also Dr. Cavit KAZAZ from Atatürk University at Erzurum-Turkey for kind assistance in the NMR analyses. Dr. Mahmoud ASLANI and B. ÇETINKAYA are acknowledged for their helpful assistance. -

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

WOS: 000248612300025This 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 mu g/l and iodine concentration ranges were within 69 +/- 26 mu g/l and 103 +/- 6 mu g/l