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Chromeo 642

Chromeo 642 (Ex-Max 642 nm/Em-Max 660 nm)

Chromeo® 642 is a bright, dark-red fluorescent label spectrally similar to Cy5*, Alexa Fluor™ 647*, DyLight™ 649* and other dyes excitable within a wavelength range of 630-650 nm. Chromeo 642 is compatible with various excitation sources including tungsten and xenon arc lamps, the Helium-Neon laser, the 647 line of the Argon-Krypton-Ion Laser and common red diode lasers with emissions of 635 nm or 650 nm. It has an excitation peak at 642 nm and an emission peak at 660 nm.

Excitation & emission spectra

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Key facts

Excitation maximum
642 nm
Emission maximum
660 nm
Optimal laser line
628-640
Optimal filter
660/20
Relative brightness
4 of 5
Extinction coefficient
180000

Chromeo 642 has an excitation maximum at 642 nm and an emission maximum at 660 nm, a Stokes shift of 18 nm. Its extinction coefficient is 180000 M⁻¹cm⁻¹. It is optimally excited by the 628-640 laser line.

Frequently asked questions

What is Chromeo 642?
Chromeo® 642 is a bright, dark-red fluorescent label spectrally similar to Cy5*, Alexa Fluor™ 647*, DyLight™ 649* and other dyes excitable within a wavelength range of 630-650 nm. Chromeo 642 is compatible with various excitation sources including tungsten and xenon arc lamps, the Helium-Neon laser, the 647 line of the Argon-Krypton-Ion Laser and common red diode lasers with emissions of 635 nm or 650 nm. It has an excitation peak at 642 nm and an emission peak at 660 nm.
What laser excites Chromeo 642?
Chromeo 642 is optimally excited by the 628-640 laser line. Its excitation maximum is 642 nm.
What filter should I use to detect Chromeo 642?
A 660/20 filter captures the peak of the Chromeo 642 emission near 660 nm with minimal spillover.
How bright is Chromeo 642?
Chromeo 642 has a relative brightness of 4 out of 5.