Molecular Beacons
Hairpin shaped hybridization probes with an internally quenched fluorophore to detect specific sequences.
Molecular Beacons are comparable with our Dual Labeled Probes. They are also available in a multitude of fluorescent dyes and quencher options. Molecular beacons, or molecular beacon probes known hybridization probes that can quenched the presence of specific nucleic acids in homogenous solutions. Beacons are hairpin like structure with an internally fluorescent dyes which act and bind to a target nucleic acid sequence.
Eurofins offer various dyes combination for synthesis in our US/Germany facility as
5' Reporter |
Abs [nm] |
Em [nm] |
3' Quencher |
FAM |
495 |
520 |
TAM, BHQ1, DAB, Eclip |
TET |
521 |
536 |
DAB |
JOE |
520 |
548 |
TAM |
HEX |
535 |
556 |
BHQ1, DAB |
Cyanine3 |
552 |
570 |
BHQ2, DAB |
ATTO 550 |
554 |
576 |
DAB |
TAMRA |
544 |
576 |
BHQ2 |
ROX |
575 |
602 |
BHQ2 |
Texas Red |
583 |
603 |
BHQ2 |
Cyanine5 |
649 |
670 |
BHQ2, BBQ650 |
Specifications
Product specifications:
- HPLC purification included
- Wobbles (non-defined ratio) possible
- TAT of 2-3 weeks
- Delivery: lyophilised or concentration adjusted in tubes
- Quality control by OD measurement and MALDI-TOF MS
Synthesis scale1 [µmol] |
0.05 |
0.2 |
1 |
Minimum Yield [nmol]2 |
5 |
15 |
30 |
Yield [OD]2 |
1-1.5 |
3 |
6 |
Length restriction |
8 to 40 |
8 to 40 |
8 to 40 |
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.