Ability to cross the cellular membrane

Some molecules improve transport through the cellular membrane:

  • The use of a specific oligonucleotide modification such as cholesterol
  • Lipophilic linkages such as methylphosphonate
  • The incorporation of modified monomers (5-(1-propynyl)-2’-deoxy-Uridine (pdU) and 5-(1-propynyl)-2’-deoxyCytidine (pdC).

Binding affinity

To increase the affinity and specificity of an RNA oligonucleotide, recommended modifications are:

  • 2’-OMe-nucleotides (2’-O-Me-RNA)
  • Phosphorothioate linkages
  • C-5 methylated pyrimidine deoxy-nucleosides
  • 5-(1-propynyl)-2’-deoxy-Uridine (pdU) and 5-(1-propynyl)-2’-deoxyCytidine (pdC) monomers