Radioiodination and biological evaluation of valsartan as a tracer for cardiovascular disorder detection
- 1 Labelled Compound Department, Hot Lab Center, Atomic Energy Authority, Cairo, Egypt
- 2 Pharmaceutics and Industrial Pharmacy Department, Faculty of Pharmacy, Cairo University, Cairo, Egypt
- 3 Radioactive Isotopes and Generators Department, Atomic Energy Authority, Cairo, Egypt
- 4 Nuclear Research Center, Atomic Energy Authority, Cairo, Egypt
- 5 Cyclotron Project, Nuclear Research Centre Atomic Energy Authority, Cairo, Egypt
Abstract
A procedure for radioiodination of valsartan with iodine-125 is carried out via an electrophilic substitution of hydrogen atom with the iodonium cation I + . All reaction parameters were studied to optimize the labeling conditions of valsartan and to obtain a maximum radiochemical yield (RCY) of the 125 I-Valsartan [ 125 I-Val]. By using 3.7 MBq of Na 125 I, 50 μg of valsartan ( 0.2 mM ) as substrate, 25 μg of Iodogen ( 0.15 mM ) as oxidizing agent in ethanol at room temperature for 30 min, the radiochemical yield of 125 I-Val was 98.6% The radiochemical yield was determined by electrophoresis using cellulose acetate moistened with 0.02 M phosphate buffer pH 7. The labeled compound was separated and purified by means of high-pressure liquid chromatography (HPLC). The biological distribution in normal mice indicates the suitability of radioiodinated valsartan to image any cardiovascular disorders.
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