UHPLC determination of oligonucleotide purity

Oligonucleotides are a rising class of drugs which have entered the market as biopharmaceuticals due to their ability to interfere directly with gene expression instead of targeting the protein. The production of oligonucleotides is usually conducted by chemical solid-phase synthesis and use of nucleoside phosphoramidites as building blocks. To prevent undesired side reactions, protecting groups are attached to the nucleosides, for example the 5’-hydroxy group of the sugar moiety is protected with a dimethoxytrityl (DMT) group.