Electron caption dissociation of proteins initiated by photoelectrons generated from 266 nm UV laser radiation on an ICR cell wall

Abstract

It was demonstrated that ECD MS can be successfully applied to Bovine ubiquitin (8.6 kDa, 76 amino acids) and Pseudomonas aeruginosa azurin (13.9 kDa, 128 amino acids, 1 disulfide bond) cations using photoelectrons emitted by irradiating a 266 nm UV laser light on the edge of an ion cyclotron resonance (ICR) cell trapping plate hole. The photoelectron ECD method cleaved protein backbone bonds as effectively as conventional ECD MS methods that employed a tungsten (W) wire or heated dispenser cathode as an electron source. This method offers the advantage of providing electrons for ECD MS without an apparent electron source.