Highest specificity with Molecular Beacons
Molecular Beacons are hairpin shaped hybridisation probes with a 3‘ fluorescent dye and 5‘ quencher. This sequence structure makes Molecular Beacons highly specific and is therefore often used in clinical or diagnostical assays.
Product specifications:
- Available synthesis scales: 0.01 - 1.0 µmol
- Probe lengths: 5-40 bases (wobbles non-defined ratio possible)
- HPLC purified by default
- TAT: 3–5 working days (1.0 µmol scale takes longer)
- Delivery format: dried or liquid at selected concentration
- QC report incl. MALDI-TOF MS spectra free of charge
A ready-to-use qPCR probe dilution buffer (10 mM Tris-HCl; 1 mM EDTA; pH 8) is provided along with all probes (1 ml for up to 3 probes).
Available dye-quencher combinations:
5' Reporter |
Abs [nm] |
Em [nm] |
3' Quencher |
Price-Cat. |
FAM |
495 |
520 |
TAM, BHQ1, DAB, Eclip |
1 |
TET |
521 |
536 |
DAB |
1 |
JOE |
520 |
548 |
TAM |
1 |
HEX |
535 |
556 |
BHQ1, DAB |
1 |
Cyanine3 |
552 |
570 |
BHQ2, DAB |
1 |
ROX |
575 |
602 |
BHQ2 |
1 |
Texas Red |
583 |
603 |
BHQ2 |
1 |
Cyanine5 |
649 |
670 |
BHQ2, BBQ650 |
1 |
Principle of molecular beacons
Molecular beacons contain a fluorescent reporter and a quencher at their 5' and 3' ends, respectively.
The sequence of these probes is designed to allow the formation of a hairpin structure in which the fluorescent dye and the quencher are in close proximity.
A molecular beacon specific for the sequence of interest is used in PCR. The probe is designed to anneal between the PCR primers.

When the probe hybridises to its target sequence in the PCR annealing step, the loop opens and the fluorescent reporter and quencher are separated, resulting in a fluorescent signal upon excitation. The amount of signal is proportional to the amount of target sequence, and is measured in real time to allow quantification of the amount of target sequence.