Texas Red azide

Sulforhodamine 101 azide (Texes Red azide) is an excellent alkyne-reactive fluorescent reagent for labeling alkyne-containing biological molecules through click chemistry. The conjugate has better solubility than the parent dye carboxyrhodamine and its long PEG spacer should reduce any steric effect of the dye on the molecule to be labelled. Sulforhodamine 101 emits at a longer wavelength than does either Tetramethylrhodamine or Sulforhodamine B. With a peak absorption at 584 nm, Sulforhodamine 101 is particularly well suited for excitation by the 568 nm spectral line of the Ar – Kr mixed gas laser commonly used in many confocal laser-scanning microscopes or the 594 nm spectral line of the orange He-Ne laser.