Compact mass spectrometer

Abstract

A miniature mass spectrometer is disclosed comprising an atmospheric pressure ionisation source, a first vacuum chamber having an atmospheric pressure sampling orifice or capillary, a second vacuum chamber located downstream of the first vacuum chamber and a third vacuum chamber located downstream of the second vacuum chamber. A first vacuum pumpis arranged and adapted to pump the first vacuum chamber, wherein the first vacuum pump is arranged and adapted to maintain the first vacuum chamber at a pressure <10 mbar. A first RF ion guideis located within the first vacuum chamber and an ion detectoris located in the third vacuum chamber. The ion path length from the atmospheric pressure sampling orifice or capillary to an ion detecting surface of the ion detectoris ≤400 mm. The mass spectrometer further comprises a tandem quadrupole mass analyser, a 3D ion trap mass analyser, a 2D or linear ion trap mass analyser, a Time of Flight mass analyser, a quadrupole-Time of Flight mass analyser or an electrostatic mass analyser arranged in the third vacuum chamber. A split flow turbomolecular vacuum pumpcomprising an intermediate or interstage port is connected to the second vacuum chamber and a high vacuum ('HV') port is connected to the third vacuum chamber. The first vacuum pumpis also arranged and adapted to act as a backing vacuum pump to the split flow turbomolecular vacuum pumpand the first vacuum pumphas a maximum pumping speed 10 m/hr (2.78 L/s).