Bio-N6-ddATP (Biotin-N6-(2’,3’-dideoxy)adenosine-5’ triphosphate) can be used for 3’-end labeling of single-stranded or double-stranded DNA. It is especially useful as a substrate for terminal transferase for the 3’-terminal addition of a single Bio-N6-ddAMP. Biotin-labeled oligonucleotides produced by this reaction are suitable as hybridization probes.

Biotin-labeled cDNA produced by this reaction can be used in nucleic acid array assays. Biotin-labeled DNA in hybridization assays can be detected by a reporter molecule linked to streptavidin, avidin, or and anti-biotin antibody. Such a complex can be detected directly, e.g. by the excitation of a fluorophore conjugated to streptavidin, or indirectly, e.g. using an enzyme conjugate that can produce an insoluble colored precipitate. Bio-N6-ddATP is also a substrate for Taq DNA Polymerase and other DNA polymerases.