Photocleavable biotin phosphoramidite for 5'-end-labeling, affinity purification and phosphorylation of synthetic oligonucleotides

Nucleic Acids Res. 1996 Jan 15;24(2):361-6. doi: 10.1093/nar/24.2.361.


We report the design, synthesis and evaluation of a non-nucleosidic photocleavable biotin phosphoramidite (PCB-phosphoramidite) which provides a simple method for purification and phosphorylation of oligonucleotides. This reagent introduces a photocleavable biotin label (PCB) on the 5'-terminal phosphate of synthetic oligonucleotides and is fully compatible with automated solid support synthesis. HPLC analysis shows that the PCB moiety is introduced predominantly on full-length sequences and is retained during cleavage of the synthetic oligonucleotide from the solid support and during subsequent deprotection with ammonia. The full-length 5-PCB-labeled oligonucleotide can then be selectively isolated from the crude oligonucleotide mixture by incubation with immobilized streptavidin. Upon irradiation with 300-350 nm light the 5'-PCB moiety is cleaved with high efficiency in <4 min, resulting in rapid release of affinity-purified 5'-phosphorylated oligonucleotides into solution. 5'-PCB-labeled oligonucleotides should be useful in a variety of applications in molecular biology, including cassette mutagenesis and PCR. As an example, PCB-phosphoramidite has been used for the synthesis, purification and phosphorylation of 50-and 60mer oligonucleotides.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Biotin / analogs & derivatives*
  • Biotin / chemical synthesis
  • Biotin / chemistry*
  • Oligonucleotides / chemical synthesis
  • Oligonucleotides / chemistry
  • Oligonucleotides / isolation & purification*
  • Oligonucleotides / metabolism*
  • Organophosphorus Compounds / chemical synthesis*
  • Organophosphorus Compounds / chemistry
  • Phosphorylation
  • Photolysis
  • Ultraviolet Rays


  • Oligonucleotides
  • Organophosphorus Compounds
  • biotin phosphoramidite
  • Biotin