CF® dye azide reacts with alkyne to form 1,2,3-triazole by copper (I) catalyzed 1,3-dipolar Huisgen cycloaddition. It could also undergo Staudinger ligation with a phosphine containing compound. CF® dyes are Biotium's line of next-generation fluorescent dyes with advantages in brightness, photostability, and conjugate specificity compared to other fluorescent dyes. Red fluorescent CF®568 dye has excitation/emission at 562/583 nm.