Gas-Phase Anion-Electron Reactions and Vibrational Activation of Nucleic Acids and Their Complexes

摘要

Tandem mass spectrometry (MS/MS) is a well established strategy for obtaining structural information of nucleic acids. Commonly employed techniques such as collision activated dissociation (CAD) and infrared multiphoton dissociation (IRMPD) may result in abundant undesired neutral base and water losses. Electron detachment dissociation (EDD), which involves electron irradiation of multiply charged anions, was demonstrated to mainly generate backbone cleavages from deprotonated oligonucleotides [1]. Recently, EDD has been applied to nucleic acids up to 61-mer [2]. Here we demonstrate the ability of activated ion (AI)-EDD to effectively dissociate 27-mer RNA anions. Electron capture dissociation (ECD) typically involves low energy electron irradiation of multiply charged cations. Here we also report that electron capture may occur for deprotonated 6-mer, 11-mer, and 27-mer oligonucleotides.