Iodo-Gen-mediated radioiodination of nucleic acids.

Iodo-Gen (1,3,4,6-tetrachloro-3a,6a-diphenylglycoluril), widely used as an oxidizing agent for iodination of proteins, can also be used for iodination of nucleic acids. Optimal conditions were determined for efficient labeling of RNA and DNA with 125I. The proposed procedure for radioiodination of nucleic acids is more beneficial than the methods utilizing TlCl3 because of the milder reaction conditions, the simplicity and completeness of separation of reaction products from the oxidizing agents, and the absence of a toxic catalyst. Using the standard procedure for Iodo-Gen-mediated iodination a specific radioactivity of up to 1.3 X 10(9) dpm/micrograms RNA can be achieved. The proposed procedure is also suitable for radioiodination of DNA.