Semrock Master Catalog 2018

TECHNICAL NOTE
Ultraviolet (UV) Fluorescence Applications
Many biological molecules of interest naturally fluoresce when excited by shorter
wavelength UV light. This “intrinsic fluorescence” can be a powerful tool as labeling
with extrinsic fluorophores is not required. One important application is the direct
fluorescence imaging of aromatic amino acids including tryptophan, tyrosine, and
phenylalanine, which are building blocks for proteins. The aromatic rings in these
molecules give rise to strong fluorescence excitation peaks in the 260 to 280 nm
range. Another application is DNA quantitation. Purines and pyrimidines – bases for
nucleic acids like DNA and RNA – have strong absorption bands in the 260 to
280 nm range.
Semrock’s UV BrightLine fluorescence filters offer a powerful tool for direct
fluorescence imaging. These unique UV filters are reliable “no burn-out” and offer
performance nearly comparable to visible and near-IR filters. Figure 1 shows the
spectrum of a high-reliability 280 nm BrightLine excitation filter with the highest
commercially available transmission (> 65%), remarkably steep edges, and wideband
blocking across the entire UV and visible spectrum. This spectrum is directly compared
to a traditional and inferior metal-dielectric filter. In one example system, this filter
difference was shown to provide over 100x improvement in signal-to-noise ratio.
Figure 2 shows the spectra from a UV filter set designed for imaging tryptophan,
overlaid on the absorption and emission spectra for that amino acid. Note the
nearly ideal overlap and high transmission of all three filters in this set.
100
UV Near-UV Visible (VIS)
90
80
70
60
50
40
BrightLine FF01-280/20 UV filter
Traditional metal-dielectric filter
30
20
10
0
200 300 400 500 600 700
Wavelength (nm)
Figure 1. BrightLine FF01-280/20-25 filter
Transmission (%)
100
90
80
Exciter
Dichroic
70
Emitter
60
50
40
30
20
10
0
250 275 300 325 350 375 400 425 450
Wavelength (nm)
Figure 2. TRP-A single-band fluorescence filter set is
ideal for imaging tryptophan (see filter set above).
Transmission (%)
Fluorophores
Single-band
Sets
Multiband
Sets
Cubes
ACTUAL MEASURED DATA
What you see is what you get. The published spectra for our filters are actual measured data from actual finished parts,
not theory and not a design estimate only to be made under ideal conditions. Our strict manufacturing control and
advanced metrology capabilities ensure that the filter you receive meets the spectral specifications you expect.
Laser
Sets
Highest Contrast FITC-2024B Set
Highest Brightness FITC-5050A Set
Transmission (%)
100
90
80
70
60
50
40
30
20
10
0
400
Dichroic
Exciter
Emitter
425 450 475 500 525 550 575 600
Wavelength (nm)
Transmission (%)
100
90
80
70
60
50
40
30
20
10
0
400
Dichroic
Exciter
Emitter
425 450 475 500 525 550 575
Wavelength (nm)
600
NLO
Filters
Individual
Filters
INDIVIDUAL & FILTER SET PACKAGING
Semrock utilizes individual PET-G packaging for standard-size
catalog filters. This packaging allows Semrock to produce cleaner
parts, reduce potential defects caused by shipping & handling, and
utilize 100% recyclable PET materials.
Custom size filters in low volume will be packaged in envelopes lined
with cleanroom grade, non-abrasive, resin-free, non-woven fabric.
Dichroic
Beamsplitters
Tunable
Filters
Learn more about our packaging at www.semrock.com/packaging.aspx
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