Terminal labeling is an ideal procedure for the labeling of oligonucleotides with haptens such as biotin or fluorescein. An oligonucleotide can be synthesized using standard, commercially available reagents and labeled after synthesis in a simple and reproducible enzyme reaction.

The BioProbe® 3'-Oligonucleotide Labeling Kit with Fluorescein-12-ddUTP contains all reagents required for terminal labeling of oligonucletides with fluorescein except the oligonucleotides to be labeled.The BioProbe® 3'-Oligonucleotide Labeling Kit provides maximum flexibility for labeling oligonucleotides approximately 15 to 100 nucleotides in length. A standard reaction will label up to 100 picomoles (1 µg of a 30-mer oligonucleotide sequence). A complete kit contains two component packs that are available separately: a Reagent Pack and a Fluorescein-12-ddUTP Dideoxynucleotide Pack. Both packs contain sufficient reagents for 25 labeling reactions.