Europium(III) trisbipyridine cryptate label for time-resolved fluorescence detection of polymerase chain reaction products fixed on a solid support.

We report a method for the nonradioactive detection of specific amplified target DNA, based on a new long-lived fluorescent label, europium(III) trisbipyridine cryptate [TBP-(Eu3+)]. After a polymerase chain reaction with a set of nested primers, microtiter affinity-collected hybrids were recognized by a TBP(Eu3+)-labeled antibody. The particular structure of the label containing the energy transfer units (bipyridine moieties) enables direct fluorescence measurement on the solid phase. Moreover, its stability and long lifetime contribute to the enhancement of the signal-to-noise ratio. The usefulness of this new label is illustrated by the detection of human papillomavirus type 16 DNA in clinical smears.