trFluor™ Fluorescent Labeling Dyes and Their Bioconjugates *Optimized for TR-FRET Applications*
Many biological compounds present in cells, serum or other biological fluids are naturally fluorescent, and thus the use of conventional, prompt fluorophores leads to serious limitations in assay sensitivity due to the high background caused by the autofluorescence of the biological molecules to be assayed. The use of long-lived fluorophores combined with time-resolved detection (a delay between excitation and emission detection) minimizes prompt fluorescence interferences.
AAT Bioquest's trFluor™ probes enable time-resolved fluorometry (TRF) for the assays that require high sensitivity. These trFluor™ probes have large Stokes shifts and extremely long emission half-lives when compared to traditional fluorophores such as Alexa Fluor or cyanine dyes. Compared to other TRF compounds, our trFluor™ probes have relatively high stability, high emission yield and ability to be linked to biomolecules. Moreover, our trFluor™ Eu probes are insensitive to fluorescence quenching when conjugated to biological polymers such as antibodies.
AAT Bioquest's trFluor™ probes enable time-resolved fluorometry (TRF) for the assays that require high sensitivity. These trFluor™ probes have large Stokes shifts and extremely long emission half-lives when compared to traditional fluorophores such as Alexa Fluor or cyanine dyes. Compared to other TRF compounds, our trFluor™ probes have relatively high stability, high emission yield and ability to be linked to biomolecules. Moreover, our trFluor™ Eu probes are insensitive to fluorescence quenching when conjugated to biological polymers such as antibodies.
Key Features of trFluor™ Dyes:
- No fluoride addition is required.
- No enhancing solution is required.
- Available in a variety of reactive forms.
- Much easier to be conjugated to biomolecules.
- Much higher conjugation yield than other TRF dyes.
- Maximally excited by the common light sources at ~350 nm.
- trFluor™ Eu dye is optimized to pair with APC, iFluor® 647,TF5, Cy5R, DyLight™ 650 and Alexa Fluor 647.
- trFluor™ Tb dye is optimized to pair with FITC, iFluor® 488, TF2, DyLight™ 488 and Alexa Fluor 488.
Table 1. Typical acceptors for the time-resolved luminescent probes
trFluor™ Donors ▲ ▼ | Recommended Acceptors ▲ ▼ |
trFluor™ Eu | iFluor® 647, TF5, APC |
trFluor™ Tb | iFluor® 488, FITC, TF2 |
Table 2. trFluor™ Eu and trFluor™ Tb specifications
Product Name ▲ ▼ | Ex (nm) ▲ ▼ | Em (nm) ▲ ▼ | Ext. Coeff. (cm-1M-1) ▲ ▼ | CF 280 nm* ▲ ▼ | CF 260 nm** ▲ ▼ |
trFluor™ Eu | 346 | 617 | ~22,000 | 0.777 | 0.911 |
trFluor™ Tb | 330 | 544 | ~20,000 | 0.797 | 0.942 |
- *CF at 260 nm is the correction factor used for eliminating the dye contribution to the absorbance at 260 nm.
- **CF at 280 nm is the correction factor used for eliminating the dye contribution to the absorbance at 280 nm (for peptides and protein labeling).
trFluor™ Eu TRF Labeling Dye
AAT Bioquest's trFluor™ Eu probes enable TRF for the assays that require high sensitivity. The trFluor™ Eu dye has large Stokes shifts and extremely long emission half-lives when compared to more traditional fluorophores such as Alexa Fluor® or cyanine dyes. Compared to other time-resolved fluorescent probes, our trFluor™ Eu probes have relatively high stability, high emission yield and ability to be linked to biomolecules with higher conjugation yield. Moreover, our trFluor™ Eu probes are insensitive to fluorescence quenching when conjugated to biological polymers such as antibodies. To maximize its TR-FRET potential, trFluor™ Eu dye is optimized to pair with APC, iFluor® 647, TF5, Cy5®, DyLight™ 650 and Alexa Fluor® 647.
trFluor™ Tb TRF Labeling Dye
The excitation and emission spectra of trFluor™ Tb Goat Anti-Rabbit IgG conjugate in PBS buffer (pH 7.2).
Table 3. trFluor™ Fluorescent Labeling Dyes and Kits
Cat No. ▲ ▼ | Product Name ▲ ▼ | Ex (nm) ▲ ▼ | Em (nm) ▲ ▼ | Unit Size ▲ ▼ |
1300 | ReadiLink™ Rapid trFluor™ Eu Antibody Labeling Kit *Microscale Optimized for Labeling 50 ug Antibody Per Reaction* | 346 | 617 | 2 Labelings |
16518 | trFluor™ Eu goat anti-mouse IgG (H+L) | 346 | 617 | 100 ug |
16668 | trFluor™ Eu goat anti-rabbit IgG (H+L) | 346 | 617 | 100 ug |
1434 | trFluor™ Eu maleimide | 346 | 617 | 100 ug |
16925 | trFluor™ Eu-streptavidin conjugate | 346 | 617 | 100 ug |
1433 | trFluor™ Eu succinimidyl ester | 346 | 617 | 1 mg |
16519 | trFluor™ Tb goat anti-mouse IgG (H+L) | 330 | 544 | 100 ug |
16669 | trFluor™ Tb goat anti-rabbit IgG (H+L) | 330 | 544 | 100 ug |
16926 | trFluor™ Tb-streptavidin conjugate | 330 | 544 | 100 ug |