Labeling Oligos with Thiazole Orange

Thiazole orange is an asymmetric cyanine dye whose fluorescence can be quite dependent on its local environment. When an oligonucleotide labeled with thiazole orange is hybridized to its complementary sequence, the thiazole orange acts as an intercalator. In addition to providing enhanced thermal stability, the dye adopts a mostly planar configuration resulting in significantly enhanced fluorescence. This “light up” effect can be as high as 34-fold depending on the sequence and how the dye is attached. This NHS ester will allow simple functionalization of internally located amino modifications such as those generated with amino-modifier C6 dT (10-1039).