Quenchers

Quenchers are a kind of chromophores that have the useful property of transforming the light energy to heat. This kind of probe design can greatly simplify many fluorescence assays because there will be no background fluorescence. Creative Biolabs provides a series of oligonucleotides modification services including quenchers, to help you understand mechanistic and stereochemical aspects of numerous biochemical reactions and processes during the phases of drug discovery and drug development.

Introduction

A quencher is a molecule that can absorb the energy emitted by a fluorophore. Through fluorescence resonance energy transfer (FRET), it emits the energy at a different wavelength, reducing the fluorescence of the fluorophore. At the same time, this quencher also acts through collisional quenching where the fluorophore and quencher are in close contact.

Fluorescence Resonance Energy Transfer (FRET) has become one of the most popular tools to assay nucleic acids. This is because FRET lends itself to high throughput automation and is quite sensitive, making it the first choice of sequence and single nucleotide polymorphism (SNP) analysis. In addition, it is highly useful for probing DNA and RNA structure, dynamics and intermolecular interactions.

Figure 1. What is FRET?

Why Use Quenchers?

Quenchers as a kind of probe design can simplify many fluorescence assays. Fluorescence-based assays are widely used in high-throughput screening because of their high sensitivity, diverse selection of fluorophores and ease of operation. Based on these, fluorescence-based assays can monitor a broad range of activities in life-science research, such as molecular dynamics and interactions, enzymatic activities, signal transduction, cell health, and distribution of molecules, organelles, or cells. Therefore, it is important to use quenchers to modify oligonucleotides.

Why Choose Us?

At Creative Biolabs, we can provide several different quenchers for customers, including dark quenchers and fluorescent quenchers. With the high quality of quenchers, our experienced staffs and technologies can help you to effectively improve the quality of oligonucleotides modification and reduce the whole time of your projects.

Types of Quenchers

Quenchers are able to absorb energy from a fluorophore (such as a fluorescent dye) and re-emitting much of the energy as either heat (in the case of dark quenchers) or visible light (in the case of fluorescent quenchers).

• Dark quenchers
  

  Dabcyl is most commonly employed as a quencher in diagnostic probes. The Dabcyl group has been identified to be a universal quencher. Dabcyl's absorption properties are restricted to those emitting at 400-550nm (absorption maximum, 471nm). Dabcyl was ideal for quenching dyes by FRET that fluoresce in the blue to green region.

• 3'-Dabcyl
  

  3'-Dabsyl CPG and 3'-Dabcyl CPG are employed to prepare probes with the quencher blocking the 3'-terminus. 3'-Dabcyl labeled oligonucleotides are employed in a wide array of applications, including dual-labeled fluorogenic probes for real-time PCR.

• 5'-Dabcyl
  

  5'-Dabcyl phosphoramidite locates at the 5'-terminus of the quencher and Dabcyl-dT places it within the sequence, leaving the 3'-terminus available for polymerase extension.

• Fluorescent quenchers
  

  Tetramethylrhodamine (TAMRA), is a kind of fluorescent quencher that has been popularly used for labeling oligonucleotides. The light-absorbing properties of TAMRA and spectral overlap with several commonly used fluorophores, including FAM, HEX, TET and JOE, make it useful as a quencher for the design of dual-labelled probes. TAMRA-modified oligonucleotides have played an important role in both FRET and real-time PCR applications.

Creative Biolabs offers many different dark and fluorescent quenchers for our clients to modify their oligonucleotides. Based on our experienced researchers and advanced technologies, we can provide high quality of oligonucleotides modifications and decrease the time of whole project for customers. If you have any special requirements in quenchers, please feel free to contact us.