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Innovations in Imaging

BMIL Data Sheet

Fluorescent light source [X-cite 120]

Above: Spectral output of X-Cite 120 Metal Halide Lamp compared to HBO 100 Watt Mercury source.
Note how X-Cite 120 is comparable in intensity initially, and it will fade less over time while the HBO lamp is retired at 200 hours.

An added benefit of X-Cite 120 is it's broader spectrum excites more fluorophores, see the table below:

Fluorophore Peak Excitation
Wavelenth (nm)
X-Cite 120
output (mW)
output (mW)
GFP/Ds Red (FRET) 471-488 8.0 2.8
FITC 490 8.1 3.0
Texas Red 595 7.0 3.3
TRITC 555 17.9 6.5
Cy3 552 27.6 12.1
Rhodamine 550 33.9 23.3
Lucifer Yellow 428 15.0 6.7


Camera Spectral Response [QImaging Retiga EXi digital camera]



Green fluorescent proteins are being used for more and more applications in molecular and cellular biology. As a result of the variety of applications several variants form the original wild type green fluorescent protein (wtGFP) have been developed. Several of these variants have different excitation and emission spectra than wtGFP.


Excitation and emission spectra of EGFP, wtGFP, and EBFP. Representative excitation (dashed lines) and emission (solid lines) spectra of the three basic GFP variants. Data was derived from reported spectra in the literature.

The red-shifted mutants have been developed for use with the standard "fluorescein" filter set and as such utilize the 485/20 excitation and 530/25 emission filter set. Note that although the 508/20 emission filter is closer to the emission peak of the sample, overlap with the 485/20 filter precludes the use of that filter, necessitating the use of the 530/25 nm filter. The blue emitting variants generally require the use of the 360/40 excitation filter in conjunction with the 460/40 emission filter.

Excitation and emission data of GFP variants

GFP Variant Excitation max (nm) Emission max (nm)
wtGFP 395 509
GFPuV 395 509
Stemmer 395 509
EGFP 488 509
GFP-S65T 489 509
Y66H 382 459
EBFP 380 460



CFSE [CellTrace™ CFSE Cell Proliferation Kit, InVitrogen]


Fluorescein goat anti mouse IgG antibody/pH 8.0


Absorption and fluorescence emission spectra of fluorescein goat anti–mouse IgG antibody in pH 8.0 buffer.


Green microspheres [FluoSpheres® polystyrene microspheres, 15 µm, green fluorescent (450/480)]

Red microsphere spectrum [FluoSpheres® polystyrene microspheres, 15 µm, red fluorescent (580/605)]

Red Quantum Dots [Qtracker® 625 Cell Labeling Kit]

Other Quantum Dots

Absorption spectra of Qdot nanocrystals plotted in terms of molar extinction coefficient.

Normalized fluorescence emission spectra of Qdot nanocrystals: 1) Qdot 525, 2) Qdot 565, 3) Qdot 585, 4) Qdot 605, 5) Qdot 625, 6) Qdot 655, 7) Qdot 705, 8) Qdot 800 nanocrystals.

the Color Spectral of Light


Dual filter spectrum [BrightLine® Pinkel filter set, optimized for Green Fluorescent Protein & DsRed and other like fluorophores]

GFP Longpass filter [GFP Longpass Emission]


RGB New Spectral Curves

The following curves were taken using a NIST-traceable visible-wavelength spectrometer and CRI-manufactured offthe-
shelf liquid crystal tunable RGB filters commonly used in the Micro*Color™ and Macro*Color™ product families.

Second-generation Micro*Color filters, which succeeded the VariSpec™ RGB filters in 1997, were phased out in late
2002 and early 2003. The filters featured a “Color-Shaping Glass” (CSG) component that helped to correct the overly
red-sensitive spectral response of most CCD-equipped cameras, produced at the time. Some OEM customers who
manufactured their own cameras with a similar CSG component purchased a “bare” Micro*Color filter with no CSG
component, but with an AR-coated cover slip.

Third-generation Micro*Color 2 filters, introduced in December of 2002, feature a near-infrared hot mirror
component, instead of the CSG. Since most camera manufacturers now include a CSG component in their visiblewavelength
models, it was decided to eliminate the CRI-supplied CSG. The hot mirror was judged to be necessary, since
many end-users utilize illumination systems, such as tungsten-halogen lamps, that output significant amounts of energy
in the near-infrared that may not be completely eliminated by a significant number of current camera configurations.