High-Resolution Electrospray Ionization Orthogonal-Injection Time-of-Flight Mass Spectrometer

A concept of an “ideal” orthogonal-injection time-of-flight (O-TOF) mass spectrometer is proposed and a new high-resolution O-TOF mass spectrometer with an electrospray ion source and a molecule-ion reactor is described. The instrument design was optimized for high resolution and sensitivity using the concept of an ideal O-TOF mass spectrometer. A mass resolving power of about 20,000 (full width at half maximum) and a mass measurement accuracy in the 10 ppm range is demonstrated.