Biotin-11-dUTP (Biotin-11-2’-deoxyuridine-5’-triphosphate, tetralithium salt) is a widely used compound for non-radioactive DNA labeling. Biotin-11-dUTP can be enzymatically incorporated into DNA via nick-translation, random priming, 3’-end terminal labeling or in the process of PCR. The number “11” is the number of carbon atoms in the backbone of linker between dUTP and biotin. The longer the linker is, the more effective interaction between biotin and avidin. On the other hand, the shorter the linker is, the more effective is the incorporation of dUTP into DNA.