Overview
DELFIA™ assays provide an excellent non-radioactive alternative to radioactive ligand-receptor binding assays. In the DELFIA assay, a Europium-labeled ligand is used (instead of radioactively-labeled ligand). The assay can be performed on membrane preparations or whole cells. View our information on labeling your own ligand. We also provide custom labeling services. DELFIA ligand-receptor binding assays can be performed on adherent cells, suspension cells, cell membranes, and prepared tissue membranes.
What do I need to run this assay?
- Appropriate plates
- For live adherent cell assays, you can use standard tissue culture-treated plates indicated for fluorescence, or you can treat cells as if they are suspension in AcroWell™ plates. For TC-treated plates, basically any color is okay, though common colors are white and clear. We usually recommend opaque white CulturPlates™.
- For membrane-based and suspension cell assays, we recommend AcroWell™ filter plates and our DELFIA L*R Binding and DELFIA L*R Wash buffers.
- Appropriate wash and binding buffers (we recommend our DELFIA L*R Wash and L*R Binding buffers for cell membrane-based filtration assays; you should not use phosphate-based buffers when the labeled reagent is in the well - see FAQs below for other buffer recommendations)
- Cell membrane, cell line, or tissue preparation to be studied; Revvity offers receptor-transfected cell lines and cell membrane preparations
- Eu-labeled ligand - view information on labeling your own ligand; we can custom-label your ligand as well
- Unlabeled ligand, agonists, and antagonists as appropriate
- DELFIA Enhancement solution
- Seal™-A adhesive plate seal (do not use adhesive seals once Enhancement solution has been added to plate)
- A TRF-capable plate reader
- Optional: Plate shaker (we recommend our DELFIA Plateshake)
- Vacuum manifold (for filtration assays)
- Optional: Plate washer (for TC-treated plate assays)
96-well Acrowell plates for filtration assays:
|
Plate supplier |
Catalog number |
|---|---|
|
Pall |
PN5020 |
|
VWR |
28148-575 |
Revvity carries cell membrane preparations and cell lines overexpressing GPCRs and other receptors.
Products and catalog numbers
View a listing of DELFIA products and catalog numbers.
Guides
- Sample protocol
Citations
View a brief listing of DELFIA ligand-binding citations.
Tips and FAQs
Q: I'm using suspension cells. Can I just use a solid plate and centrifuge when I need to wash?
A: We do not recommend this. Loss of cells can lead to signal variation. We recommend you use an AcroWell™ Filtration plate. When using whole cells, Millipore MultiScreen™ FL plates can also work.
Q. I'm performing a ligand binding assay on whole, unfixed adherent cells. What wash buffer do you recommend?A. The L*R wash concentrate is not recommended for use with whole, unfixed cells because there is no physiological concentration of sodium chloride. For a ligand binding assay using adherent, unfixed cells, we recommend using 10-15 mM Tris-HCl, 0.9% NaCl, pH 7.8 as a wash buffer. No detergent should be present in this wash buffer. You can prepare a 5X concentrate if desired. This wash solution shouldn’t be stored for more than a few days because there is no bacteriostatic agent. If a concentrate is prepared and filtered through 0.45 µm or 0.22 µm membrane, then it should be stable at +4°C at least for a few weeks.
Q. I'm performing a ligand binding assay on whole, unfixed adherent cells. What binding buffer do you recommend?A. We suggest DELFIA Assay Buffer without detergents, 5x concentrate (Cat. No. CR85-100). This assay buffer is Tris-HCl buffered (pH 7.8) salt solution with DTPA, BSA and bovine gamma globulin. CR85-100 has no divalent cation (e.g. Mg2+) but is otherwise suitable for receptor binding assays with whole cells. CR85-100 does contain a physiological concentration of NaCl.
Custom labeling and assay development services
Revvity offers custom labeling services as well as custom assay development.
For research use only. Not for use in diagnostic procedures.
The information provided above is solely for informational and research purposes only. Revvity assumes no liability or responsibility for any injuries, losses, or damages resulting from the use or misuse of the provided information, and Revvity assumes no liability for any outcomes resulting from the use or misuse of any recommendations. The information is provided on an "as is" basis without warranties of any kind. Users are responsible for determining the suitability of any recommendations for the user’s particular research. Any recommendations provided by Revvity should not be considered a substitute for a user’s own professional judgment.