Build your own protein complex for a successful Plk-1 screen!
Streptavidin-XLent HTRF®
XL665-labeled Streptavidin for capturing biotinylated proteins, peptides, antibodies, small molecules, nucleic acids....
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No-wash
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Ease-of-use
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High affinity
Overview
Streptavidin has been labeled with XL665. The streptadivin-XLent! (SA-XLent!) results from a special in-house conjugation process leading to a high grade conjugate with enhanced fluorescent properties. Biotin binds to Streptavidin with high affinity (Ka=1015M-1). The binding is rapid and stable, making it an ideal choice for use in a variety of assays such as enzyme assays, protein-protein binding assays and molecular biology assays.
Benefits
- LARGE COMPLEXES DETECTION
- BATCH-TO-BATCH REPRODUCIBILITY
- LOW TO HIGH KD DETECTION
Assay principle
In an HTRF interaction assay, one partner is labeled (directly or indirectly) with the donor, and the other with the acceptor (again, directly or indirectly). The intensity of the signal is proportional to the binding of the 2 partners. In the example shown here: Streptavidin-XLent! binds to the biotinylated partner A while partner B* binds to a specific antibody labeled to an HTRF donor. *partner B can also be tagged, Fc fused. In these cases use for the detection, the corresponding HTRF reagent (anti-Tag, anti-species, protA, Streptavidin), labeled with donor.
Assay protocol
The example on the right describes the protocol using a 20 µL final assay volume for detecting an interaction between a biotinylated-tagged partner A and a non-tagged partner B*. Dispense the 2 partners (10 µL), incubate, add Streptavidin-XLent! (5 µL) and anti-partner B labeled with acceptor (5 µL), incubate and read. *partner B can also be tagged, Fc fused or directly labeled. In these cases use for the detection, the corresponding HTRF reagent (anti-Tag, anti species, protA, Streptavidin), labeled with donor.
Build HTRF interaction assays for your specific application
Reagents are sold by the number of tests (20 µL reactions). XL665 or d2 conjugatesare supplied on the basis of 20 ng of antibody per well. The amount of active moiety per vial is also provided (as well as the number of tracers per vial - see product description sheet). The active moiety is defined as the active part of a conjugate (e.g. antibody).
How do the number of tests relate to active moiety?
The average conjugate quantity per well reflects overall biological material content. Using the active moiety amount is generally preferred to the quantity of total conjugate. For Cryptate and d2 conjugates, the total conjugate amount equals that of the active moiety, since the molecular weight of the label is negligible. This is not the case for XL665 labeled entities for which the quantity of total conjugate will vary depending on the final molar ratio of the XL665 conjugate, however, the amount of active moiety, provided by Cisbio, is constant and based on the number of tests ordered.
| Description | Active Moiety/5,000 tests |
|---|---|
| Streptavidin XLent! | 250 µg |
Recommended quantities of Cryptate and XL665 conjugates
Cryptate conjugates must not be excessive in order to prevent reader saturation and an unacceptable level of background. In most cases, a cryptate concentration of 1 to 5nM is appropriate, and will generate 20,000 to 80,000 cps at 620 nm depending on the HTRF compatible reader used. The XL665 conjugate must match its assay counterpart as closely as possible in order for the maximum number of biomolecules to be tagged with the XL665 acceptor. Thus, to detect a tagged molecule at an assay concentration of 20nM, the concentration of anti-Tag-XL665 should be equimolar or higher.
HTRF Tyrosine kinase assay
HTRF reagents (Europium-Cryptate PT66 and Streptavidin-XLent!) and conjugates from two other suppliers were used in an HTRF tyrosine kinase assay. When compared to competitor, Streptavidin-XLent! shows overall superior performance
SaXLent! compared to SaXL on the EGFR tyrosine kinase assay
Increasing quantities of EGFR were incubated with biotinylated polyGAT (50 nM). The enzymatic reaction was stopped using EDTA following a 20 minute incubation. Europium-labeled PT66 (20 ng/well) and Streptavidin-XL665 (50 nM) or StreptavidinXLent! (50 nM) were added. HTRF signal was detected following a 20 minute incubation. In addition to the increased sensitivity, over 25% less enzyme was required when using streptavidin-XLent! to produce identical assay signals.
Exploiting HTRF for novel drug classes: Stabilizing 14-3-3 protein-protein interactions
In collaboration with Lead Discovery Center GmbH - Scientific Presentations
Experience the freedom of building your own assay
HTRF kinase activity toolbox reagents - Flyers
HTRF protein-protein interaction reagents
Benefit from unlimited flexibility for your assay development - Flyers
Addressing the interactome with protein-protein assays
Cover all PPIs with one approach - Brochures
HTRF -A Beneficial Tool for Lead Optimization of Biotherapeutics
In collaboration with Boehringer Ingelheim - Posters
The ultimate guide to PPI assays with HTRF
Complete guide - Guides
Guidelines for optimizing protein-protein interaction assays using HTRF PPI reagents
Every interaction is within range - Technical Notes
Product Insert Streptavidin-ent-XL / 611SAXLA-611SAXLB
611SAXLA-611SAXLB - Product Insert
HTRF PPI your dream assay served on a plate
Sandwiches aren't just for eating - Infographics
Best practices for pharmacological characterization of PPI inhibitors
Easy pharmacological characterization of PPI modulators. - Technical Notes
HTRF assays handle low- to high affinity protein-protein interactions
Deciphering low- and high affinity interactions - Application Notes
Nuclear receptor ligand identification with HTRF
Monitoring nuclear receptor binding with HTRF assays - Application Notes
HTRF addresses large protein-protein interaction complexes
Challenge large complexes with HTRF assays - Application Notes
A brief history of Protein-Protein Interactions
How well do you know PPI? - Infographics
All your HTRF assays in one document! - Catalog
A guide to Homogeneous Time Resolved Fluorescence
General principles of HTRF - Guides
How HTRF compares to Western Blot and ELISA
Get the brochure about technology comparison. - Brochures
Virology research solutions using HTRF Protein-Protein Interaction assays
See how peer researchers challenge the viral life cycle with PPI assays - Application Notes
Advance your CAR-T cell research - Flyers
Safety Data Sheet Streptavidin-ent-XL / 611SAXLA
611SAXLA - Safety Data Sheet
Safety Data Sheet (DEU) Streptavidin-ent-XL / 611SAXLA
611SAXLA - Safety Data Sheet
Safety Data Sheet (ELL) Streptavidin-ent-XL / 611SAXLA
611SAXLA - Safety Data Sheet
Safety Data Sheet (FRA-FR) Streptavidin-ent-XL / 611SAXLA
611SAXLA - Safety Data Sheet
Safety Data Sheet (ITA) Streptavidin-ent-XL / 611SAXLA
611SAXLA - Safety Data Sheet
Safety Data Sheet (SPA) Streptavidin-ent-XL / 611SAXLA
611SAXLA - Safety Data Sheet
Safety Data Sheet (ENG-GB) Streptavidin-ent-XL / 611SAXLA
611SAXLA - Safety Data Sheet
Safety Data Sheet (ENG-US) Streptavidin-ent-XL / 611SAXLA
611SAXLA - Safety Data Sheet
Batch Information Streptavidin-ent-XL / 20230423
611SAXLA Batch 25C - Batch Information
Batch Information Streptavidin-ent-XL / 20230503
611SAXLA Batch 26A - Batch Information
Safety Data Sheet Streptavidin-ent-XL / 611SAXLB
611SAXLB - Safety Data Sheet
Safety Data Sheet (DEU) Streptavidin-ent-XL / 611SAXLB
611SAXLB - Safety Data Sheet
Safety Data Sheet (ELL) Streptavidin-ent-XL / 611SAXLB
611SAXLB - Safety Data Sheet
Safety Data Sheet (FRA-FR) Streptavidin-ent-XL / 611SAXLB
611SAXLB - Safety Data Sheet
Safety Data Sheet (ITA) Streptavidin-ent-XL / 611SAXLB
611SAXLB - Safety Data Sheet
Safety Data Sheet (SPA) Streptavidin-ent-XL / 611SAXLB
611SAXLB - Safety Data Sheet
Safety Data Sheet (ENG-GB) Streptavidin-ent-XL / 611SAXLB
611SAXLB - Safety Data Sheet
Safety Data Sheet (ENG-US) Streptavidin-ent-XL / 611SAXLB
611SAXLB - Safety Data Sheet
Batch Information Streptavidin-ent-XL / 20230108
611SAXLB Batch 25B - Batch Information
Batch Information Streptavidin-ent-XL / 20230503
611SAXLB Batch 26A - Batch Information
Plate Reader Requirement
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