Enhance the sensitivity and precision of your molecular assays with our dark quencher modification services. Dark quenchers provide highly efficient fluorescence suppression without emitting light themselves, making them ideal for a range of applications including quantitative real-time PCR, FRET probes, and molecular beacons.

Our selection of dark quenchers covers a wide spectral range, allowing for optimal quenching across different dye emissions.

Available dark quenchers

Dabcyl (DAB)

Dabcyl is a non-fluorescent quencher that effectively suppresses fluorescence in the blue to green emission spectrum. Ideal for fluorophores with emission wavelengths between 400-550 nm, it is not recommended for use with dyes emitting above 480 nm.

• Quenching range 400-550 nm
• Maximum absorbance 453 nm
• Molar extinction coefficient 32,000 M−1 cm−1
• Molecular weight 399.2 g/mol

Dabcyl-dT (DABdT)

An internal quencher variant of Dabcyl, Dabcyl-dT efficiently quenches dyes in the blue to green emission range. It can be used in combination with 3' quenchers for enhanced quenching efficiency.

• Quenching range 400-550 nm
• Maximum absorbance 453 nm
• Molar extinction coefficient 32,000 M−1 cm−1
• Molecular weight 399.2 g/mol

Eclipse (Eclip)

Eclipse is a non-fluorescent quencher from Epoch Biosciences, offering broad quenching from 390 to 625 nm. It is highly efficient for use with dual-labelled probes and molecular beacons.

• Quenching range 390-625 nm
• Maximum absorbance 522 nm
• Molar extinction coefficient 53,000 M−1 cm−1
• Molecular weight 473.9 g/mol

BHQ1 (Black hole quencher 1)

BHQ1 is a powerful quencher for green to dark yellow emission spectra, commonly used in FRET probes, molecular beacons and TaqMan chemistry.

• Quenching range 480-580 nm
• Maximum absorbance 534 nm
• Molar extinction coefficient 34,000 M−1 cm−1
• Molecular weight 491.5 g/mol

BHQ2 (black hole quencher 2)

BHQ2 extends quenching efficiency into the dark green to orange emission spectrum, making it suitable for use in dual-labelled probes with 5' fluorophores.

• Quenching range 520-650 nm
• Maximum absorbance 544 nm
• Molar extinction coefficient: 91,000 M−1 cm−1
• Molecular weight 493.5 g/mol

BBQ650 (Blackberry quencher 650)

BBQ650 is ideal for long-wavelength dyes such as Cy5 and Cy5.5, offering excellent quenching for dyes emitting in the red to near-infrared spectrum.

• Quenching range 550-750 nm
• Maximum absorbance 650 nm
• Molar extinction coefficient 41,000 M−1 cm−1
• Molecular weight 575.6 g/mol

Product specifications

• Purity: All quenchers are HPLC purified for >80% purity
• Synthesis scale: Customisable from 0.05 to 1.0 µmol
• Sequence length: Available for oligos ranging from 10 to 80 bases
• Turnaround time: Typical delivery within 3-4 weeks
• Quality control: Each oligo is rigorously tested using OD measurement and MALDI-TOF mass spectrometry to ensure precision and purity