- 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).