Solid phase synthesisof Carbon-14 labelled oligonucleotides

摘要

This paper describes the syntheses of a series of ~(14)C labelled phosphorothioate 2'-methoxy (2'-OMe) RNAs containing two ~(14)C labels. The labelled oligonucleotides were prepared by solid phase synthesis utilizing an AKTA OligoPilot 100 synthesizer and 2'-0-methyluridine[2-~(14)C]. Trityl-on purification was performed using preparative onion exchange HPLC and on-column detritylation. In addition, o ~(14)C labelled phosphorothioate 2'-OMe RNA sequence having a C6-amino spacer at the 5' terminus was synthesized and post-synthetically conjugated to a reporter group via on amide linkage. The purified phosphorothioate 2'-OMe RNAs were desalted utilizing a Millipore stir cell apparatus. These phosphorothioate 2'-OMe RNAs contained between 20 to 22 bases and were obtained on a scale of 100-200 mg with a specific activities of 10-15 μCi/mg and a radiochemical purity of greater than 95 area percent.