Why are oligonucleotides modified?

The physicochemical properties or characteristics of oligonucleotides can be modified using functional groups. Tailored modifications enable a variety of applications useful for diagnostic assays or oligonucleotide based therapeutics. Some types of modifications can be used to link or conjugate oligonucleotides to each other, to other molecules such as peptides, proteins, or carbohydrates, as well as to surfaces, for example to glass plates, microchips or microarrays.

BNAs are modified nucleotides having useful properties for the synthesis of modified oligonucleotides.

Applications and Uses

Uses for Oligonucleotides

Modification examples

Substrates for DNA ligases


Attachment to surfaces or other molecules

Linkers. Conjugation chemistry.

Detection Probes

Fluorophores. FRET. Quenchers.

3’-Blocking groups


Hybridization characteristics

Modified Bases. E.g. BNAs.

Nuclear degradation

Phosphorothioate bonds. BNAs.

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