Heat activatable 3'-modified dNTPs: synthesis and application for hot start PCR.

Several 3'-ether and 3'-ester derivatives of 2'-deoxyribonucleoside 5'-triphosphates (dNTPs) were prepared. These dNTP derivatives were not substrates for DNA polymerase and did not support primer extension at room temperature. However, by short pre-heating to 95 degrees C in PCR buffer, these 3'-modified dNTPs can be converted to corresponding unmodified natural dNTPs that efficiently support PCR amplification. The analysis of PCR products obtained with 3'-modified dNTPs revealed a significant improvement in PCR performance resulting in higher amplicon yield and reduced formation of off-target products (mis-priming and primer dimer). Among the studied 3'-modified dNTPs, the 3'-tetrahydrofuranyl derivatives showed the best results.