5-Carboxy-X-rhodamine N-succinimidyl ester (5-ROX NHS Ester) is used as an amine coupling reagent to form 5-carboxy-X-rhodamine (ROX) derivatized compounds such as proteins, nucleic acids and drugs that may be analyzed by fluorescence resonance energy transfer (FRET) and fluorescence quenching applications. Labeling reagent for preparation of charge-modified dye-labeled ddNTPs to “direct-load” DNA sequencing. Conjugates of this dye have longer-wavelength spectra than the spectra of Lisaamine™ rhodamine B conjugates, but somewhat shorter-wavelength spectra than those of Texas Red™ conjugates.


Unit Size25 mg, 100 mg, 1000 mg
ReactivityPrimary amines
Abs/Em Maxima582/606 nm
Extinction coefficient93,000 cm-1M-1
SolubilityDMSO, DMF, MeOH
Spectrally similar dyesAlexa Fluor® 568, TAMRA, CF™ 568
Molecular weight631.69
Storage Conditions-20°C.
Shipping ConditionsAmbient temperature

Abs/Em Spectra

Protein Labeling Calculator


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