5'-Biotin Phosphoramidite

CAS Number:
Catalog: Make Selections to Reveal


Biotin-dT can replace dT residues within the oligonucleotide sequence. 5'-Biotin phosphoramidite can be added ONLY ONCE to the 5'-terminus of an oligonucleotide. However, the DMT group on the biotin can be used in RP cartridge and HPLC purification techniques. PC Biotin is a photocleavable 5'-biotin phosphoramidite. BiotinTEG CPG and Protected BiotinLC Serinol CPG are designed for the direct synthesis of oligonucleotides containing biotin at the 3' terminus. Desthiobiotin is a biotin analogue that exhibits lower binding to biotin-binding proteins such as streptavidin. This biotin analogue is lacking the sulfur group from the molecule and has a dissociation constant (Kd) several orders of magnitude less than biotin/streptavidin. As a result, biomolecules containing desthiobiotin are dissociated from streptavidin simply in the presence of buffered solutions of biotin. We offer desthiobiotinTEG phosphoramidite and the corresponding CPG.



  • Coupling: 2 minute coupling time recommended
  • Deprotection: 5'-Biotin is slow to detritylate. If the final DMT-group is to be removed on the synthesizer, we recommend a second deblocking step. If the final DMT-group is left on to aid in cartridge purification, we recommend that the oligo is left in contact with the TFA solution for 10 minutes.
Diluent Anhydrous Acetonitrile
Storage Freezer storage, -10 to -30°C, dry
Stability 1-2 days

Dilution/Coupling Data

The table below show pack size data and, for solutions, dilution and approximate coupling based on normal priming procedures.

ABI 392/394

Catalog # Pack Size Grams/Pack 0.1M Dil. (mL) Approximate Number of Additions
LV40 LV200 40nm 0.2μm 1μm 10μm
10-5950-02 0.25 g .25grams 2.95 85 51 31.88 23.18 17 4.25
10-5950-90 100 µmol .085grams 1 20 12 7.5 5.45 4 1
10-5950-95 50 µmol .042grams 0.5 3.33 2 1.25 0.91 0.67 0.17


Catalog # Pack Size Grams/Pack Dilution (mL) Approximate Number of Additions
Molarity 50nm 0.2μm 1μm 15μm
10-5950-02 0.25 g .25grams 4.41 0.07 81.8 51.13 37.18 5.11
10-5950-90 100 µmol .085grams 1.5 0.07 23.6 14.75 10.73 1.48
10-5950-95 50 µmol .042grams 0.75 0.07 8.6 5.38 3.91 0.54

Product FAQs

  • What absorbance does biotin have at 260nm? The HPLC trace shows absorbance at 254nm?
  • Do you have a biotin phosphoramidite containing a disulfide linker which can be cleaved later with DTT to release the DNA from a streptavidin support?
  • How can I tell if the biotinylated oligonucleotide I have made really does contain biotin?
  • Can oligonucleotides modified at the 5'-terminus with, for example, biotin be phosphorylated with kinase?