Cy5 Azide

The far-red fluorescent Cy5 azide can be reacted with terminal alkynes via a copper-catalyzed click reaction (CuAAC). It also reacts with strained cyclooctyne via a copper-free “click chemistry” reaction to form a stable triazole and does not require Cu-catalyst or elevated temperatures. This far-red fluorescent probe is water-soluble, and its fluorescence is pH-insensitive from pH 4 to pH 10. Its excitation peak is ideally suited for the 633 nm or 647 nm laser lines and its absorption and emission spectra are almost identical to those of Alexa Fluor® 647, CF® 647 Dye, or any other Cyanine5 based fluorescent dyes.