A probe for detection of G-rich target strands through fluorescence quenching

A modified fluorescent probe U(F)AA AAT CTC CGC CGC was synthesized using the nucleoside analogue 3'-O-(N,N'-diisopropylamino-2-cyanoethoxyphosphinyl)-5'-O-(4,4'-dimethoxytrityl)-2'-O-(dansyl-1-sulfonamidohexylaminocarbonyl)uridine for hybridization studies with perfectly matched (U/A) complementary DNA and with a DNA strand having similar G-rich telomeric units at their 3'-ends. Data on the thermal stability and decrease in fluorescence intensity due to the presence of dG units clearly demonstrated the potential application of this approach in DNA diagnostics in homogeneous hybridization assays.