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Updated: Jan 20, 2026

A Novel Saturation Mutagenesis Approach: Single Step Characterization of Regulatory Protein Binding Sites in RNA Using Phosphorothioates
Published on: August 21, 2018
Studying the Biotransformation of Phosphorothioate-Containing Oligonucleotide Drugs by LC-MS
Christophe Husser1, Erich Koller1, Andreas Brink1
1Roche Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland.
Abstract:
Across the pharmaceutical industry, there is increasing interest and need to investigate the biotransformation of oligonucleotide drugs. The method of choice is high-resolution mass spectrometry due to its unmet sensitivity and specificity.Here, we describe a method developed and applied in our laboratory studying the biotransformation of phosphorothioate-containing oligonucleotide drugs. This method is based on capillary flow liquid chromatography with column switching coupled to high-resolution mass spectrometry.
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