AnaSpec, a subsidiary of Eurogentec, is pleased to highlight our Double-Dye Oligo Synthesis Service. With over 20 years expertise of oligonucleotide synthesis, and production facilities in San Diego, California and Liege, Belgium, we offer the largest number of fluorescent reporters and quenchers available in the industry. Furthermore, for applications such as genotyping or gene expression profiling, requiring small amounts of several different probes, we have developed a high-throughput platform capable of producing high quality small scale Real-Time qPCR Double-Dye probes. All Double-Dye Probes are HPLC purified. They are QC’d by analytical HPLC and MALDI-TOF Mass Spectrometry and are provided lyophilized in individual tubes.

Double-Dye Oligonucleotides have a fluorescent reporter dye and a quencher at their 5’ and 3’ ends, respectively. These oligos are designed to anneal between the upstream and downstream PCR primers. The higher Tm of the Double-Dye Oligonucleotide probe compared to the Tm of the upstream primer ensures that the primer is already being extended while the Double-Dye Oligonucleotide probe is not yet annealed. The optimal recommended length of Double-Dye Oligonucleotide probes is 25 bases, and maximum length is 30 bases. For extra long Double-Dye Oligonucleotides probes, quenchers like Black Hole Quencher™, Deep Dark Quencher I and TAMRA can be coupled internally.


During the amplification process, the 5’>3’ exonuclease activity of the Taq DNA polymerase cleaves the fluorophore from the probe. Since the fluorophore is no longer subjected to FRET quenching, it fluoresces. This fluorescence can be measured, and the level is directly proportional to the amount of accumulating target DNA during the PCR reaction. 

Click here to view a table recommending the best fluorophore/quencher combination for each qPCR platform, on a channel basis.

Click here for instant pricing and convenient online ordering on Eurogentec’s website.