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A Versatile and Convenient Synthesis of ³⁴ S-Labeled Phosphorothioate Oligonucleotides.

ABSTRACT: A synthetic protocol for ³⁴ S-labeled phosphorothioate oligonucleotides (PS ONs) was developed to facilitate MS-based assay analysis. This was enabled by a highly efficient, two-step, one-pot synthesis of ³⁴ S-labeled phenylacetyl disulfide (³⁴ S-PADS), starting from ³⁴ S-enriched elemental sulfur (³⁴ S₈ ). ³⁴ S-PADS was subsequently used for stable isotope labeling (SIL) of oligonucleotides containing a phosphorothioate backbone. The ³⁴ S-SIL PS ONs are shown to retain the same melting temperature, antisense activity, and secondary structure as those of the corresponding unlabeled ³² S PS ONs.

SUBMITTER: Stulz R

PROVIDER: S-EPMC6585993 | biostudies-literature |

REPOSITORIES: biostudies-literature

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