One of the limiting factors in determining the sensitivity of tandem mass spectrometry using
hybrid quadrupole orthogonal acceleration time-of-flight instruments is the duty cycle of the
orthogonal ion injection system. As a consequence, only a fraction of the generated
fragment ion beam is collected by the time-of-flight analyzer. Here we describe a method
utilizing postfragmentation ion mobility spectrometry of peptide fragment ions in conjunction
with mobility time synchronized orthogonal ion injection leading to a substantially improved …