Overview
DELFIA assays require a plate reader that is capable of TRF (time-resolved fluorescence) detection. This is a time-resolved fluorescence intensity assay. We recommend using a Revvity VICTOR™ Nivo, VICTOR™ X, EnSight™, EnVision™, or EnSpire™ Multilabel Plate Reader (view our instrument product pages). If you are using a plate reader manufactured by another company, you can use our Europium standard solution (catalog number B119-100) and perform a serial dilution in DELFIA Enhancement solution to determine the sensitivity of your instrument. We also offer Samarium standard solution (catalog number B115-100) and Terbium standard solution (catalog number C558-100) if you are interested in multiplexing.
- Fluorometers (filter fluorometer) vs. spectrofluorometers/monochromators
We recommend a time-resolved filter-based fluorometer for DELFIA Europium assays. Very sensitive time-resolved spectrofluorometers may be suitable for certain assays. Most plate readers are capable of TRF-type assays - a flash lamp is needed for TRF analysis, which is an option on most plate readers. You could also use laser excitation on an appropriate EnVision instrument.- A TRF filter fluorometer plate reader utilizes bandwidth filters in front of the fiber optic for excitation and in front of the detector for emission wavelength choice. The grating-type spectrofluorometers are generally less sensitive than filter fluorometers, and loss in sensitivity can cause issues in highly sensitive assays such as TRF.
- A TRF-capable spectrofluorometer utilizes a monochromator (usually an excitation and emission grating) to discriminate wavelength positions of study for fluorescence excitation and emission. Spectrofluorometers can be up to 1000-fold less sensitive than filter fluorometers, though spectrofluorometers may work in some DELFIA applications.
- The new double-monochromator instruments claim to have almost similar sensitivity as the ‘original’ filter readers. These may be suitable for most DELFIA assays.
- For cell-based assays, top illumination is recommended, as some clear-bottom plates may absorb excitation at 340 nm. Top illumination is naturally required with white and black plates.
- DELFIA Instrument Settings when using DELFIA Europium
We recommend generic default instrument settings for all DELFIA assays. We always recommend you check with the manufacturer of your particular instrument to see if they have additional recommendations for DELFIA assays.
Table: Settings for Revvity instruments
| General | VICTOR Nivo | EnSight | EnVision | EnSpire | VICTOR X | |
|---|---|---|---|---|---|---|
| Excitation | 320 or 340 wide-banded filter | 320/75nm (HH35000947) | UV (TRF340) dug11 + wg320 filter, barcode 101 (HH34005010) | UV (TRF340) dug11 + wg320 filter, barcode 101 (2100-5010) | UV (TRF340) dug11 + wg320 filter, (2300-5010) | 340/60 nm (built-in in VICTOR X4 and X5) |
| Emission | 615nm narrow filter bandwidth | 615/8nm (HH35000935) | 615nm (monochromator setting) | Europium 615/8.5 nm, barcode 203 (2100-5090) | 615nm (monochromator setting) | 616/8.5 nm (11440003) |
| Dichroic | D400 (HH35000971) | n/a | LANCE/DELFIA D400 single mirror, barcode 412 (2100-4170) | n/a | n/a | |
| Delay | 400µsec | 400µsec | 200µsec | 400µsec | 200µsec | 400µsec |
| Window | 400µsec | 400µsec | 400µsec | 400µsec | 400µsec | 400µsec |
| Other settings | Measurement time: 500ms | Number of Sequential Windows: 1 | Number of sequential windows: 1 | Number of Sequential Windows: 1 | Counting cycle: 1000µsec | |
| Flash energy: 100mJ | Number of Flashes: 100 | Number of flashes: 100 | Number of Flashes: 100 | Flash energy mode: High | ||
| Time between flashes: 2000µsec |
- DELFIA Instrument Settings when using DELFIA Terbium
- Settings for a filter fluorometer:
- Excitation: 340 nm
- Emission: 545 nm
- Delay: 500 µsec
- Window: 1400 µsec
- Cycle: 2000 µsec
-
Flash energy: high
If you are working with Terbium and/or Samarium, please view the measurement information on our DELFIA multiplexing page.
- Settings for a filter fluorometer:
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.