Luminescence Switching by Hybridization-Directed Mixed Lanthanide Complex Formation

We have developed a homogeneous assay method in which the lanthanide ion carrier and light absorbing components of a luminescent lanthanide chelate are separated in two distinct molecules that can together form a luminescent mixed chelate complex. The separated label moieties were conjugated to oligonucleotides which were used as probes to detect a complementary target DNA. The background signal of the assay was very low, indicating the signal was highly dependent on the hybridization of the two probes on adjacent positions on the target oligonucleotide.