Sequence determination of multiply charged peptide molecular ions by electrospray–ionization tandem mass spectrometry

Abstract
Electrospray ionization generates multiply charged peptide molecular ions which are efficiently dissociated by collision with a neutral gas to provide sequence‐specific daughter ions. The scope for application of this phenomenon is illustrated by the nearly complete sequencing of melittin (relative molecular mass (Mr) 2846.5) employing a tandem quadrupole mass spectrometer having a mass limit of m/z 1400.