Terbium bromide

The recognition of the limitations of short radiative fluorescence lifetime of some covalently bound labels used in studies of nucleic acids prompted Saavedra and Picozza to bind terbium to DNA via inunobilized DTPA [47]. Instead of the nanosecond lifetimes achieved with stains such as ethidium bromide, a radiative lifetime of 1.5 msec was obtained for terbium-labeled DNA. In addition, this material is stable under the conditions frequently encountered in polyacrylamide gel electrophoresis. This labeling technique could also be used for RNA. There can be no doubt that the requirements of genetic manipulation will bring about many similar procedures for analyzing nucleic acids. 

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