Psoralen C6 can be incorporate into oligonucleotide at any position at time of synthesis. This heterocyclic compound contain a C6 linker are often used facilitate oligonucleotide's ability to intercalating between bases, and cross-link bases, in both double-stranded and triple-stranded DNA for the purpose of probing nucleic acid secondary structure. When exposure to long wavelength UV light (350 nm), psoralen can form two different adducts with thymidine: 1) monoadduct, in which the psoralen moiety binds to one adjacent thymidine on the same or complimentary strand. 2) diadduct, in which psoralen binds to two thymidines adjacent to it, either on the same or complimentary strand 2 . Diadducts formed between adjacent thymidines are photo-reversable with short wavelength UV light (254 nm). In addition to cross-linking duplex DNA, Psoralen-C6 homopyrimidine oligos can be used to bind to a complementary homopurine-homopyrimidine duplex, to form a triple-helix that can then be cross-linked together at the triplex-duplex junction point 3 . Psoralen-modified oligonucleotides are widely used as research tools; representative examples of such use are shown in these references 4,5 .

Contact Bio-Synthesis for Psoralen C6 Intercalator Oligonucleotide Modification.

Product Information


Product Name:

Psoralen C6 Oligonucleotide Modification


Intercalators, Cross-link base

Modification Code:


Chemical Formula:


Exact Mass:


Formula Weight:



406.12 (100%), 407.12 (22.2%), 408.12 (3.7%)

Elemental Analysis:

C, 59.11; H, 5.71; O, 27.56; P, 7.62


Bio-Synthesis Inc. Oligo Structure



Delivery Format:


Shipping Conditions:

Room Temperature

Storage Conditions:

-20°C To -70°C
Oligonucleotides are stable in solution at 4°C for up to 2 weeks. Properly reconstituted material stored at -20°C should be stable for at least 6 months. Dried DNA (when kept at -20°C) in a nuclease-free environment should be stable for years.



  1. Cimino, G.D., Gamper, H.B., Isaacs, S.T., Hearst, J.E. Psoralens as Photoactive Probes of Nucleic Acid Structure and Function: Organic Chemistry, Photochemistry, and Biochemistry. Ann. Rev. Biochem. (1985), 54: 1151-1193.
  2. Pieles, U., Englisch, U. Psoralen covalently linked to oligodeoxyribonucleotides: synthesis, sequence specific recognition of DNA and photo-cross-linking to pyrimidine residues of DNA. Nucleic Acids Res. (1989), 17: 285-299.
  3. Takasugi, M., Guendouz, A., Chassignol, M., Decout, J.L., Lhomme, J., Thuong, N.T., Helene, C. Sequence-specific photo-induced cross-linking of the two strands of double-helical DNA by a psoralen covalently linked to a triple-helix-forming oligonucleotide.Proc. Natl. Acad. Sci. USA (1991), 88: 5602-5606.
  4. Barre, F-X., Ait-Si-Ali, S., Giovannangeli, C., Luis, R., et al. Unambiguous demonstration of triple-helix-directed gene modification. Proc. Natl. Acad. Sci. USA (2000), 97: 3084-3088.
  5. Wang, X., Peterson, C.A., Zheng, H., Nairn, R.S., Legerski, R.J., Lei, L. Involvement of Nucleotide Excision Repair in a Recombination-Independent and Error-Prone Pathway of DNA Interstrand Cross-Link Repair.Mol. Cell. Biol. (2001), 21: 713-720. - Psoralen C6