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MB 633 NHS Ester (FP-1771)



For many years, the cyanine-5 based dye (Cy™5 and more recently Alexa Fluor® 647) has been the dye of choice in far-red spectral window due to minimal autofluorescence in most biological samples in this spectral region allowing for extremely sensitive detection. In spite of recent improvement in cyanine-5 based dyes most dye are still lacks sufficient photostability required for many demanding applications.

MB 633 is a novel, rhodamine-based dye with its absorption peak at 630 nm. MB 633 can be optimally excited by the 633 nm He-Ne laser or the 635 nm red diode laser with emission maximum at 650 nm. The most important advantage of MB 633 and other rhodamine-based far-red MB dyes are their unmatched photostability. The combination of superior brightness and photostability makes far-red MB dyes ideal choices for detection in the long wavelength region on a variety of instruments


Unit Size1 mg, 5 mg, 25 mg, 100 mg
ReactivityPrimary amine
Abs/Em Maxima630/650 nm
Extinction coefficient100,000 cm-1M-1
SolubilityWater, DMSO, DMF
Spectrally similar dyesAlexa Fluor® 633, CF® 633,
Molecular weight1095.11
Storage Conditions-20°C.
Shipping ConditionsAmbient temperature

Abs/Em Spectra

MB633 MB633

Protein Labeling Calculator


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