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Core Concepts
Scientific Fundamentals Explained

Increase oligo stability with phosphorothioate modifications


Quick Facts:

  • Availability: DNA or RNA
  • Scales: 100 nmole to large scale
  • Purification: HPLC or PAGE
  • Symbol (for ordering through IDT): * placed between two nucleotides

Phosphorothioate bonds substitute a sulfur atom for one of the non-bridging oxygen atoms in the phosphate backbone of an oligonucleotide. Phosphorothioates are primarily incorporated to prevent nuclease degradation. Substituting a sulfur atom for an oxygen atom renders the internucleotide linkage resistant to both endo- and exonucleases. Placing this modification between nucleotides at either terminus of an oligonucleotide sequence will provide exonuclease protection, while using the modification internally will inhibit endonuclease degradation. To order, place an asterisk (*) between two nucleotides, indicating the bond you would like to modify (e.g., A*CTG*ATCG*A).

See what other modifications are available from IDT. You can find a list of standard modifications we make to oligonucleotides on the Modifications page of our online catalog. And if you don’t find what you are looking for, just send us a request. We often synthesize special, non-catalog requests. Contact us at noncat@idtdna.com

1 Comment

  1. 1 Tennyson 28 May
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