A TOF mass spectrometer for the study of noncovalent complexes

► We have constructed a new time-of-flight mass spectrometer with ESI source. ► Accelerating voltage of 16 kV improves both transmission and detection efficiency. ► Quadrupole ion cooling and a two-stage ion mirror give mass resolution up to 18,000. ► High m/z compounds can be seen with no resolution loss at low m/z. ► The mass accuracy for noncovalent compounds is in the range of 30-40 ppm.