Autoradiolysis of labeled organic compounds

The growing diversity of labeled chemicals in use, some of which are extrem ely labile, and a wide spectrum of available radionuclides (including ultra -short-lived) in various chemical and physical forms, as well as the use of compounds with exceedingly high specific activity make it necessary to dis cuss in detail the modern state of the autoradiolysis problem. Along with c omprehensive characterization of this phenomenon, we extended in this revie w the concept of autoradiolysis and discussed certain effects closely relat ed to self-decomposition and distorting the experimental results or hinderi ng synthesis of labeled compounds. The modern definition of the radioisotop ic (radionuclide) and radiochemical purity is given. Various types of autor adiolysis are considered (primary internal autoradiolysis, primary external autoradiolysis, and secondary autoradiolysis), and ways of quantitative ev aluation of autoradiolysis are discussed. The effects of storage conditions and specific sensitivity on the stability of labeled compounds are discuss ed. The effect of autoradiolysis on the possibility of using labeled substa nces is considered, in particular, the radiation-induced hydrogen isotope e xchange of organic compounds in water. Some peculiar practical applications of autoradiolysis are presented. The main methods for protection from auto radiolysis are discussed.