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 爱游戏平台注册登录 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 爱游戏平台注册登录 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 Flash energy: 100mJ	Number of Sequential Windows: 1 Number of Flashes: 100	Number of sequential windows: 1 Number of flashes: 100 Time between flashes: 2000µsec	Number of Sequential Windows: 1 Number of Flashes: 100	Counting cycle: 1000µsec Flash energy mode: High

  
  

  • 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.