Design, simulation and evaluation of improved air amplifier incorporating an ion funnel for nano-ESI MS

Investigation by simulation of the RF carpets for the transport of ions at atmospheric pressures

Ion funnels, quadrupole, and multipole are well-known ion optic methods for transportation of ions. However, the methods are suitable for pressures below 30-40 Torr. The main loss of ions occurs in an inlet of mass spectrometer at atmospheric pressure. This work offers a focusing system, which employs a fine-structure electrode ion carpet. The focusing efficiency of fine-structure electrode was investigated by computer simulation methods and it was compared with theoretical estimation. The methods demonstrated good agreement with each other that promises a reliability of results. The authors found an optimal fine-structure electrode ion carpet configuration (electrodes width of 10 µm), which demonstrates suitable focusing efficiency and can be implemented in practice.