Chemical Sequencing of Phosphorothioate Oligonucleotides Using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry

摘要

A new technique for sequencing phosphorothioate oligo- nucleotides is demonstrated that uses matrix-assisted laser desorption/ionization time-of-flight mass spectrum- etry (MALDI-TOFMS). Current sequencing protocols for phosphorothioate analysis have drawbacks to their wide- spread implementation. Enzymatic and Maxam-Gilbert sequencing techniques require oxidation to the phos- phodiester moiety, thereby increasing analysis time and eliminating the ability to locate modified linkages.