Dual-Labeled Probes

Choose Dual-Labeled Probes for:

  • Microarray validation
  • Multiply target genes / few samples
  • Pathogen detection
  • Multiplexing
  • Viral load quantification
  • Gene expression analysis
  • Gene copy determination

Perfect for validating MISSION® siRNA and shRNA knockdowns.

Benefits of Using Dual-Labeled Probes include:

  • Design simplicity for sequence specificity
  • Extensive availability of reporter/quencher combinations
  • Increased sensitivity

Add LNA to Your Probe for:

  • Increased thermal stability and hybridization specificity
  • Greater accuracy in SNP detection, allele discrimination, and in vitro quantification or detection
  • Easier and more sensitive probe designs for problematic target sequences

How Dual-Labeled Probes Work

A Dual-Labeled Probe is a single-stranded oligonucleotide labeled with two different dyes. A reporter dye is located at the 5’ end and a quencher molecule located at the 3’ end. The quencher molecule inhibits the natural fluorescence emission of the reporter by fluorescence resonance energy transfer (FRET). The illustration below depicts the mechanism.

How Dual-Labeled Probes Work

The primer is elongated by the polymerase and the probe binds to the specific DNA template. Hydrolysis releases the reporter from the probe/target hybrid, causing an increase in fluorescence. The measured fluorescence signal is directly proportional to the amount of target DNA.

Product Features include:

  • Amounts: 1, 3, 5, and 10 OD
  • Purification: HPLC
  • Sequence Lengths: 15 - 40 bases
  • Quality Control: 100% mass spectrometry
  • Format: Supplied dry in amber tubes
  • Custom formats available (normalization, special plates, etc.)

Sigma's probes are provided in a format to simplify your experimental planning.

Guaranteed Yields

Guaranteed
OD Yield
Approx. No.
of nmoles
Approx. No.
of µg
Approx. No.
of Reactions*
1 4 32 800
3 12 96 2,400
5 20 160 4,000
10 40 320 8,000

*Estimate is based on 4 nmoles or 32 µg for 1 OD and 200 nM in 25 µl reaction (5.0 pmol/reaction). Estimate is based on an average sequence length of 25 bases.

Spectral Properties Table

Dye Max.
EX (nm)
Max.
EM (nm)
Compatible
Quencher
6-FAM™ 494 515 BHQ®-1, TAMRA™
JOE™ 520 548 BHQ-1, TAMRA
TET™ 521 536 BHQ-1, TAMRA
Cal Fluor® Gold 5401 522 541 BHQ-1
HEX™2 535 555 BHQ-1, TAMRA
Cal Fluor Orange 5602 540 561 BHQ-1
TAMRA 555 576 BHQ-2
Cyanine 3 550 570 BHQ-2
Quasar® 5703 548 566 BHQ-2
Cal Fluor Red 5904 565 588 BHQ-2
ROX™ 573 602 BHQ-2
Texas Red® 583 603 BHQ-2
Cyanine 5 651 674 BHQ-3
Quasar 6705 647 667 BHQ-3
Cyanine 5.5 675 694 BHQ-3

1JOE/TET alternative
2VIC® alternative
3Cyanine 3 alternative
4TAMRA alternative
5Cyanine 5 alternative

Materials