Copper complex-assisted DNA hybridization

2,2`-Bipyridine ( bpy) or 1,10-phenanthroline ( phen) metal-binding domains were covalently attached to oligonucleotides, and the influence of metal ions on the hybridization of the conjugates was investigated. Metal-binding domains were attached to oligonucleotides at 3`- and 5`-terminal positions, thus placing them in juxtaposed positions after hybridization to a common target strand. While the ligands alone had a positive effect ( increased T-m) on hybrid stability, the duplex was further stabilized by the addition of copper( I) and/or copper( II) through the formation of a metal complex in which the two short sequences are linked through Cu( bpy)(2)