Preparation of [8-3H] adenosine-5'-triphosphate of high molar activity

A method of synthesis of [8-3H]adenosine-5'-triphosphate with a molar activity greater than 10 Ci/mmol and radiochemical purity better than 95 % was elaborated. It was found in tracer experiments on catalytic reduction dehalogenation of 8-bromoadenosine-5'-triphosphate that the highest molar activities could be obtained by 1N ammonium hydroxide. Catalytic phosphorylation of [8-3H]adenosine-5'-monophosphate was studied in the presence of the enzymatic preparation from Escherichia coli B. [8-3H]adenosine-5'-triphosphate was prepared with a yield of 64.4 %. The dependence on pH of hydrogen isotopic exchange in [8-3H]adenosine-5'-triphosphate in an aqueous medium (100 0C, 1 hour) was investigated. The isotope exchange was found to be significantly accelerated in alkaline media. (author)