Linker and Spacer Phosphoramidites

The addition of primary amine groups to oligonucleotides are utilized to attach a variety of modifiers (eg. NHS ester fluors) or the attachment to a solid surface. Choose from either 5′-Aminohexyl Linker or TFA-amino linker to add a primary amine to the 5' position of your oligonucleotide sequence.  Or for the addition of a phosphate to the 5' position, choose phosphorylating amidite.  All three can be found below in the Linkers drop down menu. Spacer phosphoramidites can be utilized to change the oligonucleotide conformation and/or reduce steric hinderance for applications such as aptamers and tagging/labeling assays.  

Process and supply chain control

  • Processes are monitored from material procurement through final QC and product release, providing batch-to-batch reproducibility
  • A controlled raw material supply chain and established vendor partnerships ensure consistency and security of supply
  • Purity of each spacer-modified phosphoramidite lot is assessed by HPLC and 31P NMR analyses
  • Rigorously controlled manufacturing processes minimize levels of reactive P(III) impurities which could be incorporated into the oligonucleotide and result in the accumulation of by-products

Flexible packaging

  • Common oligo synthesizer pack sizes are available for immediate delivery
  • Custom and bulk packaging are also available. Contact us to learn more.

Custom services

  • Custom manufacturing services are available to assist in the development or scale-up of phosphoramidite compounds
  • Specialty phosphoramidites can be manufactured with base or sugar (2′, 3′ or 5′ positions) modifications


Not finding what you are looking for? We also offer DNA phosphoramiditesRNA phosphoramiditesspecialty phosphoramiditesdye-labeled phosphoramidites2′-modifications, and succinates and CPG support synthesis supportsContact us to learn more.