A mini mass spectrometer with a low noise Faraday detector

An ion trap mass spectrometer is conventionally featured with an electron multiplier as its detector. However, an electron multiplier can typically work at pressures below 20 mTorr with a high voltage applied, which limits the further miniaturization of ion trap mass spectrometers. In this work, a low noise Faraday detector was developed and integrated in our miniature mass spectrometer instrument, and a post data processing method was applied to improve its performance. A limit of detection of 1 ng mL-1 was achieved, and quantitation performance and mass resolution were characterized. This technology could be useful in the further development of miniature mass spectrometers by increasing background pressures.