Figure 17 Dose response curves illustrating the inhibition of binding by blocking antibodies.

DNA hybridization and related enzyme assays using nucleic acid binding partners can be conducted in solution using HTRF. A simple measure of hybridization was conducted using one oligonucleotide directly labeled with (Eu)K, while the complementary strand was biotinylated and labeled with streptavidin-XL665. The extent to which the complementary strands are bound can be measured by the HTRF signal that results from the proximity of the two fluorophores [11]. The fol-lowing assays were more recently developed to measure nucleic acid-related enzyme activity.