CF® dye-dUTP can be used for TUNEL assay, or to synthesize labeled DNA probes for in situ hybridization and nucleic acid blotting applications. CF® dyes are Biotium's line of next-generation fluorescent dyes with advantages in brightness, photostability, and conjugate specificity compared to other fluorescent dyes. Blue fluorescent CF®405S dye has excitation/emission at 404/431 nm.