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Ibrahim I.T.,Hot Laboratories Center | Walyb M.A.,Mansoura University | El-Tawoosya M.,Hot Laboratories Center
Radiochemistry | Year: 2012

Quinoxaline 1,4-dioxide derivative, 2-{[benzyl(cyanomethyl)amino]methyl}-3- (ethoxycarbonyl) quinoxaline 1,4-dioxide (Q 3D), was synthesized and labeled with radioiodine via direct electrophilic substitution giving labeling yield above 90%. The product was examined by paper electrophoresis. 125I-Q 3D was prepared using Chloramine T as oxidizing agent. 125I-Q 3D was stable for up to 72 h post labeling, in contrast to 99mTc-AQCD which is stable only for a short time. Biodistribution study of 125I-Q 3D in ascites tumor bearing mice revealed large uptake of the labeled compound in tumor sites. In addition, in vitro incubation of the labeled compound with Ehrlich cells indicated incorporation of these compounds in DNA of tumor cells. This uptake of 125I-Q 3D in DNA of tumor cells may be helpful in tumor diagnosis and therapy. © Pleiades Publishing, Inc., 2012.


Amin A.M.,Hot Laboratories Center | Ibrahim I.T.,Hot Laboratories Center | Attallah K.M.,University of Umm Al - Qura | Ali S.M.,Hot Laboratories Center
Radiochemistry | Year: 2014

Sulfadimidine, a bacteriostatic drug blocking folic acid synthesis, was labeled with 99m Tc producing a yield of about 90%. The optimum conditions required to obtain 90% yield of the 99m Tc complex were as follows: 500 μg of sulfadimidine, 100 μg of SnCl2· 2H2O, 5 min, room temperature (25 ± 1 C), pH 4 (0.5 M citrate buffer). The radiochemical purity of the labeled compound was determined using paper and thin-layer chromatography. Biodistribution study in normal mice showed high uptake of the 99m Tc complex in stomach and intestine. The ratio of the uptake of the 99m Tc complex in muscles infected with E. coli to that in normal mice was about 2, 1.5 and 1.4 at 15, 90, and 180 min post injection, respectively, whereas for the muscles inflamed with heat-killed E. coli or sterile turpentine oil the difference from the normal muscles was insignificant. © 2014 Pleiades Publishing, Inc.


El-Azony K.M.,Hot Laboratories Center
Applied Radiation and Isotopes | Year: 2011

A separation procedure of 64,67Cu(II) from 65Zn(II) was studied for serving 62Zn/ 62Cu generator preparation. The distribution coefficients of 65Zn(II) and 64,67Cu(II) ions from homogeneous medium of hydrochloric acid and acetone onto De-Acidite FF anion exchanger were investigated. Both hydrochloric acid and acetone concentrations are important factors that affect the separation process. Effects of decreasing the HCl concentration from 0.2 to 0.04M, increasing the acetone concentration from 5% to 80% and different acetone concentrations (5-97%) in 0.2M HCl were also studied on the separation of 64,67Cu(II) from 65Zn(II). The exchange capacity of Zn(II) on the De-Acidite FF matrix was obtained as 3.8meq/g and the 64,67Cu(II) elution efficiency was 92.5% using 20ml of 0.2M HCl-60% acetone with flow rate of 2ml/min.The radionuclidic purity and radiochemical purity of the eluted 64,67Cu(II) were examined. © 2011 Elsevier Ltd.


Sanad M.H.,Hot Laboratories Center
Radiochemistry | Year: 2013

Omeprazole, a proton pump inhibitor, was labeled with 99m Tc to obtain 99m Tc-omeprazole in ∼96% yield in basic media. The optimum conditions were as follows: pH 9, 50 μg of SnCl2· 2H2O, 30 min, and 3 mg of the substrate. 99m Tc-omeprazole was stable for 6 h. Intravenous biodistribution of 99m Tc-omeprazole showed that it concentrated in the stomach ulcer to reach about 22% of the total injected dose at 1 h post injection. This concentration of 99m Tc-omeprazole in stomach ulcer may be sufficient for ulcer imaging. © 2013 Pleiades Publishing, Inc.


El-Tawoosy M.,Hot Laboratories Center
Radiochemistry | Year: 2013

A simple, fast, and efficient method was developed for preparing radioiodinated 125I-pindolol (125IPIN) using different oxidizing agents. 125I-PIN was prepared by the reaction between Na125I and pindolol using iodogen, Chloramine-T, N-bromosuccinamide, or H2O2 as an oxidizing agent at pH 7. The reaction proceeds well within 30 min at room temperature (20-25 C). The radiochemical yield was determined by TLC using chloroform-acetic acid-water (15: 4: 1) as developing solvent and by HPLC using reversed-phase RP18 column and acetonitrile-0.1 M ammonium bicarbonate (pH 7.5) (1: 1) as the mobile phase at a flow rate of 1 mL min-1. The radiochemical yield with the above oxidants was found to be 85, 93, 96.5, and 97.5%, respectively, with the radiochemical purity of 125I-PIN over 99.9%. © 2013 Pleiades Publishing, Inc.


Farouk N.,Hot Laboratories Center | El-Tawoosy M.,Hot Laboratories Center | Ayoub S.,Hot Laboratories Center | El-Bayoumy A.S.,Hot Laboratories Center
Journal of Radioanalytical and Nuclear Chemistry | Year: 2011

Celecoxib was labelled effectively with 99mTc. The labeling yield was found to be influenced by the amount of celecoxib, the amount of stannous chloride dihydrate, the reaction time, the temperature and the pH of the reaction mixture. The importance of stannous chloride dihydrate arises from its function as a reducing agent for pertechnetate to form complex celecoxib. The suitable amount required to produce high labeling yield of 99mTccelecoxib was 500 lg SnCl 2.2H 2O. The pH of the reaction medium was found to play a significant role in this labeling process. The labeling reaction was performed at a neutral medium (pH 7). The labeling reaction proceeds well at room temperature (25 ± 1 °C) and the complex decomposes by heat. The labeled celecoxib ( 99mTc- celecoxib) showed a good localization in inflamed foci and a good imaging must be taken 4 h post injection. © Akadémiai Kiadó, Budapest, Hungary 2011.


Tadros N.A.,Hot Laboratories Center | El-Sweify F.H.,Hot Laboratories Center
Journal of Radioanalytical and Nuclear Chemistry | Year: 2011

In the Egyptian society, it is usual until now that females wear extensively gold jewelry since their birth. The present work is carried out to determine gold content in scalp hair samples from some selected female donors of various ages. Instrumental Neutron Activation Analysis, with gamma ray spectrometry was applied for this study. The obtained data are compared with the available published data for analysis of hair samples from other countries. The correlation between age and gold concentration in hair samples is discussed. Interpretation of the influence of other factors which possibly may affect the contents of gold in the analyzed hair samples is also presented. © 2011 Akadémiai Kiadó, Budapest, Hungary.


Sanad M.H.,Hot Laboratories Center | El-Tawoosy M.,Hot Laboratories Center
Journal of Radioanalytical and Nuclear Chemistry | Year: 2013

An adopted method for the preparation of high radiochemical purity 99mTc-ursodeoxycholic acid (UDCA) was conducted with a high radiochemical yield up to 97.5 %. The reaction proceeds well using 2 mg UDCA, 50 μg tin chloride in solution of pH 8 at room temperature for 30 min. The radiochemical yield was up to 97.5 % as pure as 99mTc-UDCA. Different chromatographic techniques (paper chromatography and electrophoresis) were used to evaluate the radiochemical yield and purity of the labeled product. Biodistribution studies were carried out in Albino Swiss mice at different time intervals after administration of 99mTc-UDCA. The uptake of 99mTc-UDCA in the liver gave the chance to diagnose it. The results indicate that the labeled compound cleared from the systematic circulation within 2 h after administration and majority of organs showed significant decrease in uptake of 99mTc-UDCA. Finally, the liver uptake was high and the results indicate the possibility of using 99mTc-UDCA for hepatobiliary imaging. © 2013 Akadémiai Kiadó, Budapest, Hungary.


Abdel-Azi H.M.,Hot Laboratories Center | El-Zahhar A.A.,Hot Laboratories Center | Siyam T.,Hot Laboratories Center
Journal of Applied Polymer Science | Year: 2012

In this study, a procedure for preparation of organic-inorganic composite was established. The procedure was based on gamma irradiation polymerization of polyacrylamide (PAAm) in presence of maleic acid (MA), clay minerals [kaolinite (K)], or [montmorillonite (M)] and methylenebisacrylamide (NMBA) as a crosslinker. The functionality of the produced adsorbents were assayed using FTIR spectroscopy, SEM, and XRD and were evaluated for sorption of neutral red (NR) dye from aqueous solutions via batch sorption experiments. Various factors influencing the sorption behavior (e.g., pH, sorbent dose, and dye concentration) were studied. The sorption data fitted well with Langmuir isotherm model. Batch kinetic experiments showed that the adsorption followed pseudosecond-order kinetic model with correlation coefficients greater than 0.999. © 2011 Wiley Periodicals, Inc.


El-Tawoosy M.,Hot Laboratories Center | Ibrahim I.T.,Hot Laboratories Center
Radiochemistry | Year: 2012

A procedure for preparing high-radiochemical-purity 125I- salbutamol was developed in order to characterize the binding properties of β2-adrenoceptors. Direct radioiodination of salbutamol was carried out using Chloramine T as an oxidizing agent. The optimized conditions for salbutamol labeling with 125I are as follows: 100 μg of salbutamol, 50 μg of Chloramine T, 150 μl of phosphate buffer (pH 7), room temperature (25 ± 1°C), 5 min. The radiochemical yield of up to 98% was attained. The radiochemical yield and purity of the labeled product were evaluated by electrophoresis and HPLC. Biodistribution studies were carried out in normal Albino Swiss mice at different time intervals after administration of 125I-salbutamol. The results indicate that the labeled compound cleared from the systematic circulation within 3 h after administration and majority of organs showed significant decrease in the the 125I- salbutamolI-salbutamol uptake. The heart and lung uptake was high. 125I-Salbutamol can be used as β-receptor imaging agent. © Pleiades Publishing, Inc., 2012.

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