Biotin-16-dUTP can be enzymatically incorporated into DNA via nick translation, random priming, or 3′ end terminal labeling. The terminal deoxynucleotidyl transferase (TdT)-mediated biotin-dUTP nick end-labeling (TUNEL) method has been commonly used for apoptosis studies. The number ’16’ is the number of atoms in the linker between biotin and dUTP. The length of the linker affects the incorporation efficiency of the biotin-dUTP probe into DNA using DNA polymerases, and it also affects biotin/avidin or biotin/streptavidin. In general, the shorter the linker, the more efficiently the biotin-dUTP is incorporated into DNA by DNA polymerases. On the other hand, the longer the linker, the better biotin can interact with avidin or streptavidin. Properties: Colorless liquid; Store at -20⁰C; C32H48N7O18P3SLi; MW: 971.5.