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Oligo modifications

A wide variety of modifications can be incorporated into an oligo at the time of synthesis. Some modifications, however, must be attached after synthesis, using NHS Ester chemistry. These post-synthesis modifications often result in lower yields, as they require HPLC purification.

For detailed information about the modifications we offer, click on any of the categories below. Note that not all modifications are available for all types of products and sequences. If the modification you need is not listed, please contact

Fluorophores and dark quenchers »

Fluorescent dyes re-emit light upon excitation while dark quenchers absorb the emitted light and release heat. These modifications are added to oligos that are used in a variety of molecular biology applications. Browse our Freedom™ Dyes, which have no patent licensing restrictions, or the full catalog of fluorophores and dark quenchers.

Attachment chemistry and linkers »

Link an oligonucleotide with another molecule or a particular surface. Subcategories include biotins, amino-modifiers, alkynes, and thiol Modifiers, as well as Azide, Digoxigenin, and Cholesteryl-TEG.