Multifunctional oligopyridines for application in biological and materials chemistry

The influence of a metal complex formation on the hybridisation of oligodeoxynucleotides
was investigated. Incorporation of the metal-binding domains had a positive influence on the
hybrid. Addition of copper(I) or copper(II) ions results in the formation of metal complexes
and leads to substantial further stabilization. The placement of the metal-free ligands had no
influence on the extent of the stabilization. The stabilizing effect obtained by metalcoordination
was found to be distance-dependent.
This study showed that hybridisation of relatively short (13- and 8-mer) oligonucleotides
modified with bpy or phen metal-binding domains to a complementary target DNA is assisted
by formation of metallonucleotides containing {Cu(bpy)2}, {Cu(phen)2} or {Cu(bpy)(phen)}
domains.
The study of photochemistry of disubstituted-2,2´-bipyridine and 2,9´-disubstituted-1,10-
phenanthroline copper(I) complexes showed that compound with triphenylamine substituents
are very fluorescent.
We can imagine now the preparation and investigation of novel types of arrays containing
oligonucleotide metal conjugates. Arrays of this type should allow the direct detection and
quantification of nucleotic acids (DNA). The basic concept consists of the generation of a
fluorescent metal complex upon hybridisation of analyte nucleic acid to substrate bound
oligonucleotides containing metal binding ligands substituted with triphenylamine in the
presence of a second, oligonucleotide-ligand conjugate and appropriate metal ion.